Bhagya

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Tamilnadu Samacheer Kalvi 10th Science Solutions Chapter 2 Optics

Samacheer Kalvi 10th Science Optics Text Book Back Questions and Answers

I. Choose the correct answer.

Question 1.
The refractive index of four substances A, B, C and D are 1.31,1.43,1.33, 2.4 respectively. The speed of light is maximum in:
(a) A
(b) B
(c) C
(d) D
Answer:
(a) A

Question 2.
Where should an object be placed so that a real and inverted image of same size is obtained by a convex lens:
(a) f
(b) 2f
(c) infinity
(d) between f and 2f
Answer:
(b) 2f

Question 3.
Where should an object be placed so that a real and inverted image of the same size is obtained by a convex lens ______.
(a) f
(b) 2f
(c) infinity
(d) between f and 2f.
Answer:
(b) 2f

Question 4.
Magnification of a convex lens is _____.
(a) positive
(b) negative
(c) either positive or negative
(d) zero.
Answer:
(b) negative

Question 5.
A convex lens forms a real, diminished point sized image at focus. Then the position of the object is at:
(a) focus
(b) infinity
(c) at 2f
(d) between f and 2f
Answer:
(b) infinity

Question 6.
Power of a lens is -4D, then its focal length is:
(a) 4 m
(b) -40 m
(c) -0.25 m
(d) -2.5 m
Answer:
(d) -2.5 m

Question 7.
In a myopic eye, the image of the object is formed _____.
(a) behind the retina
(b) on the retina
(c) in front of the retina
(d) on the blind spot.
Answer:
(c) in front of the retina

Question 8.
The eye defect ‘presbyopia’ can be corrected by:
(a) convex lens
(b) concave lens
(c) convex mirror
(d) Bi focal lenses
Answer:
(d) Bi focal lenses

Question 9.
Which of the following lens would you prefer to use while reading small letters found in a dictionary?
(a) A convex lens of focal length 5 cm
(b) A concave lens of focal length 5 cm
(c) A convex lens of focal length 10 cm
(d) A concave lens of focal length 10 cm
Answer:
(d) A concave lens of focal length 10 cm

Question 10.
If V_B, V_G, V_R be the velocity of blue, green and red light respectively in a glass prism, then which of the following statement gives the correct relation?
(a) V_B = V_G = V_R
(b) V_B > V_G > V_R
(c) V_B < V_G < V_R
(d) V_B < V_G > V_R
Answer:
(c) V_B < V_G < V_R

II. Fill in the blanks.

1. The path of the light is called as ………
2. The refractive index of a transparent medium is always greater than ……….
3. If the energy of incident beam and the scattered beam are same, then the ………. scattering of light is called as scattering ……….
4. According to Rayleigh’s scattering law, the amount of scattering of light is inversely proportional to the fourth power of its ……….
5. Amount of light entering into the eye is controlled by ……….

Answer:

1. ray
2. unity
3. elastic
4. wavelength
5. iris

III. True or False. If false correct it.

1. Velocity of light is greater in denser medium than in rarer medium.
2. The power of lens depends on the focal length of the lens.
3. Increase in the converging power of eye lens cause ‘hypermetropia’
4. The convex lens always gives small virtual image.

Answer:

1. False – Velocity of light is greater in rarer medium than in denser medium.
2. True
3. True
4. False – The convex lens does not give small virtual image always.

IV. Match the following.

Answer:
1. d
2. a
3. e
4. b
5. c

V. Assertion and reasoning type.

Mark the correct choice as-
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
1. Assertion: If the refractive index of the medium is high (denser medium) the velocity of the light in that medium will be small
Reason: Refractive index of the medium is inversely proportional to the velocity of the light.

2. Assertion: Myopia is due to the increase in the converging power of eye lens.
Reason: Myopia can be corrected with the help of concave lens.
Answer:
1. (a)
2. (a)

VI. Answer Briefly.

Question 1.
What is refractive index?
Answer:
Refractive index gives us an idea of how fast or how slow light travels in a medium.

Question 2.
State Snell’s law.
Answer:
The ratio of the sine of the angle of incidence and sine of the angle of refraction is equal to the ratio of refractive indices of the two media. This law is also known as Snell’s law.
\(\frac{sin i}{sin r}\) = \(\frac{µ_2}{µ_1}\)

Question 3.
Draw a ray diagram to show the image formed by a convex lens when the object is placed between F and 2F.
Answer:

Question 4.
Define dispersion of light.
Answer:
When a beam of white light or composite light is refracted through any transparent media such as glass or water, it is split into its component colours. This phenomenon is called as ‘dispersion of light’.

Question 5.
State Rayleigh’s law of scattering.
Answer:
Rayleigh’s scattering law states that, “The amount of scattering of light is inversely proportional to the fourth power of its wavelength”.
Amount of scattering ‘S’ ∝\(\frac{1}{λ^4}\)

Question 6.
Differentiate convex lens and concave lens.
Answer:

Question 7.
What is the power of accommodation of the eye?
Answer:

• The ability of the eye lens to focus nearby as well as the distant objects is called the power of accommodation of the eye.
• This is achieved by changing the focal length of the eye lens with the help of ciliary muscles.

Question 8.
What are the causes of ‘Myopia’?
Answer:

1. The lengthening of eye ball.
2. The focal length of eye lens is reduced.
3. The distance between eye lens and retina increases.
4. The far point will not be at infinity.
5. The far point comes closer.

Question 9.
Why does the sky appear blue in colour?
Answer:
When sunlight passes through the atmosphere, the blue colour (shorter wavelength) is scattered to a greater extent than the red colour (longer wavelength). This scattering causes the sky to appear blue in colour.

Question 10.
Why are traffic signals red in colour?
Answer:

• Red light has the highest wavelength.
• It is scattered by atmospheric particles.
• So red light is able to travel the longest distance through a fog, rain etc.

VII. Give the answer in detail.

Question 1.
List any five properties of light?
Answer:

• Light is a form of energy.
• Light always travels along a straight line.
• Light does not need any medium for its propagation. It can even travel through a vacuum.
• The speed of light in vacuum or air is, c = 3 × 10⁸ ms^-1
• Since light is in the form of waves, it is characterized by a wavelength (λ) and a frequency (v), which are related by the following equation: c = vλ (c = velocity of light).
• Different coloured light has a different wavelength and frequency.

Question 2.
Explain the rules for obtaining images formed by a convex lens with the help of ray diagram.
Answer:
Rule-1: When a ray of light strikes the convex or concave lens obliquely at its optical centre, it continues to follow its path without any deviation.

Rule-2: When rays parallel to the principal axis strikes a convex or concave lens, the refracted rays are converged to (convex lens) or appear to diverge from (concave lens) the principal focus.

Rule-3: When a ray passing through (convex lens) or directed towards (concave lens) the principal focus strikes a convex or concave lens, the refracted ray will be parallel to the principal axis.

Question 3.
Differentiate the eye defects: Myopia and Hypermetropia.
Answer:

Question 4.
Explain the construction and working of a ‘Compound Microscope’.
Answer:
Construction : A compound microscope consists of two convex lenses. The lens with the shorter focal length is placed near the object, and is called as ‘objective lens’ or ‘objective piece’. The lens with larger focal length and larger aperture placed near the observer’s eye is called as ‘eye lens’ or ‘eye piece’. Both the lenses are fixed in a narrow tube with adjustable provision.

Working : The object (AB) is placed at a distance slightly greater than the focal length of objective lens (u > F₀). A real, inverted and magnified image (A’B’) is formed at the other side of the objective lens. This image behaves as the object for the eye lens. The position of the eye lens is adjusted in such a way, that the image (B’B’) falls within the principal focus of the eye piece. This eye piece forms a virtual, enlarged and erect image (A”B”) on the same side of the object.

Compound microscope has 50 to 200 times more magnification power than simple microscope.

VIII. Numerical Problems.

Question 1.
An object is placed at a distance 20 cm from a convex lens of focal length 10 cm. Find the image distance and nature of the image.
Answer:
Distance of an object u = 20 cm
Focal length of a convex lens f = 10 cm
Let the image distance be v
We know

v = 20 cm
Magnification m = \(\frac{v}{u}\) = \(\frac{20}{20}\) = 1
Hence a real image of same size is formed at 20 cm.
Image distance = 20 cm

Question 2.
An object of height 3 cm is placed at 10 cm from a concave lens of focal length 15 cm. Find the size of the image.
Answer:
Object distance u = 10 cm
Focal length of a concave lens f= -15 cm
Let v be the image distance,

Distance of image v = 6 cm
Magnification m = \(\frac{v}{u}\) = \(\frac{6}{10}\) = 0.6
And Magnification m = \(\frac{h’}{h}\)
Where h’ – height of image
h – height of object
0.6 = \(\frac{h’}{3}\)
∴ h’ = 3 × 0.6 = 1.8 cm
∴ Height of image = 1.8 cm

IX. Higher order thinking (HOT) questions.

Question 1.
While doing an experiment for the determination of focal length of a convex lens, Raja Suddenly dropped the lens. It got broken into two halves along the axis. If he continues his experiment with the same lens,
(a) can he get the image?
(b) Is there any change in the focal length?
Answer:
(a) He can get the image.
(b) The focal length of the lens will be doubled.

Question 2.
The eyes of the nocturnal birds like owl are having a large cornea and a large pupil. How does it help them?
Answer:

• The large pupil opens wider and allows the maximum amount of light to enter the eye in the dark.
• Their lens is large and situated near the retina. This also allows a lot of light to register on the retina. The retina contains 2 types of light-sensing cells rods and cones.
• Cones are responsible for the coloured vision and require bright, focused light.
• Rods are extremely sensitive to light and have a photosensitive pigment called rhodopsin which plays a vital role in night vision.

Samacheer Kalvi 10th Science Optics Additional Important Questions and Answers

I. Choose the correct answer.

Question 1.
The scattering of sun light by the atoms or molecules of the gases in the Earth’s atmosphere is known as:
(a) Mie scattering
(b) Tyndall scattering
(c) Rayleigh scattering
(d) Raman scattering
Answer:
(c) Rayleigh scattering

Question 2.
Mie scattering is responsible for the _____ appearance of the clouds.
(a) red
(b) blue
(c) colourless
(d) white.
Answer:
(d) white

Question 3.
In an inelastic scattering the energy of the incident beam of light is ……….. that of scattering beam.
(a) greater than
(b) less than
(c) equal to
(d) different from
Answer:
(d) different from

Question 4.
As per Rayleigh’s scattering law, amount of scattering is:
(a) directly proportioanl to fourth power of wavelength
(b) inversely proportioanl to fourth power of wavelength
(c) inversely proportioanl to square of wavelength
(d) directly proportional to square of wavelength
Answer:
(b) inversely proportioanl to fourth power of wavelength

Question 5.
The refractive index of a medium is dependent on the _____ of the light.
(a) wavelength
(b) strength
(c) density
(d) refraction.
Answer:
(a) wavelength

Question 6.
The scattering of light by colloidal particles in the colloidal solution is called:
(a) Raman scattering
(b) Tyndall scattering
(c) Mie scattering
(d) Elastic scattering
Answer:
(b) Tyndall scattering

Question 7.
A piece of transparent material bounded by curved surfaces is called:
(a) mirror
(b) prism
(c) slab
(d) lens
Answer:
(d) lens

Question 8.
If the energy of the incident and the scattered beam of light are not the same, then it is called as _____.
(a) Elastic
(b) Raman
(c) Inelastic
(d) Mie.
Answer:
(c) Inelastic

Question 9.
A convex lens does not produce:
(a) real magnified image
(b) virtual magnified image
(c) virtual diminished image
(d) real diminished image
Answer:
(c) virtual diminished image

Question 10.
A lens which is thicker in the middle than at the edges is known as:
(a) concave lens
(b) convex lens
(c) bifocal lens
(d) cylindrical lens
Answer:
(b) convex lens

Question 11.
The object is always placed on the _____ side of the lens.
(a) left
(b) right
(c) top
(d) bottom.
Answer:
(a) left

Question 12.
The parallel rays from the outer edge are deviated towards the middle in a:
(a) convex mirror
(b) concave lens
(c) concave mirror
(d) convex lens
Answer:
(d) convex lens

Question 13.
The light rays passing through the optic centre will:
(a) diverged
(b) scattered
(c) converged
(d) emerge undeviated
Answer:
(d) emerge undeviated

Question 14.
All the distances are measured from the ______ of the lense.
(a) centre of curvature
(b) optical centre
(c) principal focus
(d) infinity.
Answer:
(b) optical centre

Question 15.
A ray passing through the principal focus and incident on the lens will:
(a) converge
(b) diverge
(c) emerge parallel to the principal axis
(d) not emerge out
Answer:
(c) emerge parallel to the principal axis

Question 16.
When the object is placed at infinity from the convex lens, the image is formed at:
(a) F
(b) C
(c) infinity
(d) between F and 2F
Answer:
(a) F

Question 17.
The human eye is ____ in nature.
(a) convex
(b) concave
(c) transparent glass
(d) Plano – concave.
Answer:
(a) convex

Question 18.
The image formed by a concave lens is:
(a) virtual
(b) diminished
(c) virtual and diminished
(d) virtual and enlarged
Answer:
(c) virtual and diminished

Question 19.
To get a real image using convex lens, the object must be placed at:
(a) infinity
(b) principal focus
(c) beyond principal focus and infinity
(d) both (b) and (c)
Answer:
(d) both (b) and (c)

Question 20.
_____ is the centre part of the iris.
(a) cornea
(b) retina
(c) pupil
(d) eye lens.
Answer:
(c) pupil

Question 21.
For a convex lens the point at which the parallel rays converge is called of the lens.
(a) pole
(b) centre of curvature
(c) principal focus
(d) none
Answer:
(c) principal focus

Question 22.
A real image formed by a convex lens is always:
(a) erect
(b) magnified
(c) inverted
(d) diminished
Answer:
(c) inverted

Question 23.
The law of distances is given by:

Answer:
(b) \(\frac{1}{f}\) = \(\frac{1}{u}\) + \(\frac{1}{v}\)

Question 24.
The unit of focal length is:
(a) dioptre
(b) metre
(c) ohm
(d) ampere
Answer:
(b) metre

Question 25.
The sign of focal length of a convex lens is ………. sign.
(a) negative
(b) positive
(c) negative or positive
(d) none of the above
Answer:
(b) positive

Question 26.
The focal length of concave lens has ……… sign.
(a) positive
(b) negative
(c) positive or negative
(d) none of the above
Answer:
(b) negative

Question 27.
The magnification in terms of object distance u and image distance v is m :
(a) \(\frac{u}{v}\)
(b) u + v
(c) \(\frac{v}{u}\)
(d) uv
Answer:
(c) \(\frac{v}{u}\)

Question 28.
In terms of object distance u and focal length/, magnification is given by m =

Answer:
(b) \(\frac{f}{u-f}\)

Question 29.
The magnification in terms of v and/:
(a) f
(b) v – f
(c) \(\frac{f}{v-f}\)
(d) \(\frac{v-f}{f}\)
Answer:
(d) \(\frac{v-f}{f}\)

Question 30.
The unit of power is:
(a) m
(b) ohm
(C) dioptre
(d) ampere
Answer:
(C) dioptre

Question 31.
If the focal length of a convex lens is 1 m then its power is:
(a) 1 dioptre
(b) 0.1 dioptre
(c) 10 dioptre
(d) 0.01 dioptre
Answer:
(a) 1 dioptre

Question 32.
In a simple microscope, the magnification can be increased by:
(a) lens of long focal length
(b) lens
(c) lens of short focal length
(d) lens of infinite focal length
Answer:
(c) lens of short focal length

Question 33.
Convex lenses are used:
(a) as camera lenses
(b) as magnifying lenses
(c) to correct hypermetropia
(d) all the above
Answer:
(d) all the above

Question 34.
Which lens is used in wide angle spyhole in doors?
(a) convex lens
(b) concave lens
(c) cylindrical lens
(d) parabolic lens
Answer:
(b) concave lens

Question 35.
The mathematical form of lens maker’s formula is:

Answer:
(a)

Question 36.
If f is the focal length of the lens then its power is given by:
(a) P = \(\frac{2}{f}\)
(b) p = \(\frac{1}{f}\)
(c) p = f
(d) p = f₁
Answer:
(b) p = \(\frac{1}{f}\)

Question 37.
Which part of the human eye changes the focal length of the eye lens?
(a) pupil
(b) retina
(c) ciliary muscles
(d) cornea
Answer:
(c) ciliary muscles

Question 38.
On which part of human eye, image is formed?
(a) cornea
(b) iris
(c) retina
(d) pupil
Answer:
(c) retina

Question 39.
For normal human eye the value of near point is:
(a) 25 cm
(b) 25 m
(c) 2.5 m
(d) 25 mm
Answer:
(a) 25 cm

Question 40.
In hypermeteropia, the focal length of the eye lens is:
(a) decreased
(b) remains the same
(c) increased
(d) none of the above
Answer:
(c) increased

Question 41.
Presbyopia can be corrected by using:
(a) convex lens
(b) bifocal lens
(c) concave lens
(d) cylindrical lens
Answer:
(b) bifocal lens

Question 42.
Astigmatism can be corrected by using:
(a) bifocal lens
(b) cylindrical lens
(c) convex lens
(d) concave lens
Answer:
(b) cylindrical lens

Question 43.
The magnifying power of compound microscope is:
(a) 10
(b) 20
(c) 50
(d) 50 to 200
Answer:
(d) 50 to 200

Question 44.
The accuracy of travelling microscope is of the order of:
(a) 0.01 cm
(b) 0.01 mm
(c) 0.1 mm
(d) 0.1 cm
Answer:
(b) 0.01 mm

II. Fill in the blanks.

1. The velocity of light in vacuum is ……….
2. If v is the frequency and λ is the wavelength then velocity of the wave is c = ……….
3. Among colours of visible light ……… colour has the highest wavelength.
4. According to Snell’s law refractive index, µ₂ = ……….
5. In a medium having high value of refractive index then speed of light in that medium is ……….
6. Angle of refraction is the smallest for ……… and the highest for ……….
7. The refractive index depends on ………. of light.
8. Colours having shorter wavelength scattered more than longer wavelength colours according to ……….. law.
9. After passing through a convex lens ……….. rays ………. at the principal focus.
10. For a convex lens, as the object distance increases, the image distance ……….
11. A ray passing through the optic centre of a lens emerges …………
12. ……… is due to irregular curvature of the surface of the eye lens.
13. When a parallel beam of light passes through a convex lens, the rays from the outer edges are …………
14. A ray parallel to the principal axis of a convex lens after refraction passes through …………
15. When the object is placed between ………….. and ………… of a convex lens a virtual image will be formed.
16. For a convex lens, as the object approaches the lens the image becomes …………
17. In a phographic camera ………… lens is used.
18. The shorter the focal length, the ………. is the magnification.
19. The nature of the image formed by a simple microscope is ……….., ………… and …………
20. Real images are formed by a ……….. lens.
21. Concave lens produces ………… images.
22. The value of power of a lens having focal length one metre is ………..
23. For a normal eye the value of far point is …………
24. …………. is known as short sightedness.
25. Hyper metropia is known as ………..
26. The mathematical form of focal length of a concave lens used to correct myopia is f = ……….
27. ……….. lenses are used to correct astigmatism.
28. For a normal eye, the value of least distance of distinct vision is ………..
29. The objective of the compound microscope has …………. focal length.
30. The focal length of ………. is greater in a compound microscope.
31. ……… is an optical instrument to see the distant objects.
32. A terrestrial telescope produces ……… image.
33. Elaborate view of galaxies and planets is obtained by ………
Answer:
1. 3 × 10⁸ m/s
2. vλ
3. red
4. \(\frac{sin i}{sin r}\)
5. low
6. red, violet
7. wavelength
8. Rayleigh scattering
9. parallel, converge
10. will decrease
11. undeviated
12. Astigmatism
13. deviated towards the centre of the lens
14. the principal focus
15. principal focus, optical centre
16. bigger
17. biconvex
18. greater
19. virtual, erect, magnified
20. convex
21. virtual
22. One dioptre
23. infinity
24. Myopia
25. long sightedness
26. xy/x – y
27. Cylindrical
28. 25 cm
29. shorter
30. eye piece
31. Telescope
32. an erect
33. Telescope

III. True or False. If false correct it.

1. Light does not travel along a straight line.
2. All coloured light has same wavelength.
3. In refraction incident ray, refracted ray and normal lie in the same plane.
4. Velocity of light is greater in rarer medium is greater than that in denser medium.
5. For red colour angle of refraction is the least.
6. The refractive index of a medium ¡s independent of wavelength.
7. Tyndall scattering, is the scattering of light by colloids.
8. According to Rayleigh’s scattering law, red colour is scattered to a greater extent than blue colour.
9. Mie scattering takes place when the diameter is larger than the wavelength of the incident light.
10. The lines in Raman scattering having frequencies lower than the incident frequency are called Antistoke’s lines.
11. In front of a convex lens when the object is placed at infinity the formed image is smaller than that of the object.
12. When an object is placed at finite distance from the concave lens a virtual image is formed between optical centre and focus of the concave lens.
13. Pupil of human eye bends the incident light on to the lens.
14. For a normal human eye, the value of far point is 25 cm.
15. Astigmatism is corrected by cylindrical lenses.
Answer:
1. False – Light always travels along a straight lines.
2. False – Different coloured light has different wavelength.
3. True
4. True
5. True
6. False – The refractive index of a medium depends on wavelength.
7. True
8. False – According to Rayleigh’s scattering law, blue colour is scattered to a greater extent than red colour.
9. True
10. False – The lines in Raman scattering having frequencies higher than the incident frequency are called Antistoke’s lines.
11. True
12. True
13. False – Cornea of human eye bends the incident light on to the lens.
14. False – For a normal human eye, the value of near point is 25 cm.
15. True

IV. Match the following.

Question 1.
Match the column I with column II.

Answer:
A. (v)
B. (iv)
C. (i)
D. (ii)

Question 2.
Position of the object placed infront of a convex lens are given in Column
I. Match them with the natures of the images formed by the convex lens given in column II.

Answer:
A. (v)
B. (iv)
C. (i)
D. (ii)

Question 3.
Match the following:

Answer:
A. (v)
B. (iv)
C. (i)
D. (ii)

Question 4.
Match the Column I with Column II.

Answer:
A. (iv)
B. (iii)
C. (ii)
D. (i)

Question 5.
Match the Column I with Column II.

Answer:
A. (iv)
B. (i)
C. (ii)
D. (iii)

Question 6.
Match the column I with column II.

Answer:
A. (iii)
B. (i)
C. (iv)
D. (ii)

Question 7.
Match the Column I with Column II.

Answer:
A. (iv)
B. (iii)
C. (ii)
D. (i)

V. Assertion and Reasoning type.

Question 1.
Assertion : The sun looks bigger in size at sunrise and sunset than during day.
Reason : In detraction light rays bend around the edges of the obstacle.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

Question 2.
Assertion: Colours can be scan in thin layers of oil on the surface water. Reason: White light is composed of several colours.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

Question 3.
Assertion: Raman spectrum of a liquids contains lines whose frequencies are not equal to that of incident radiation.
Reason: If a photon strikes an atom in a liquid that is in existed state photon losses energy.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

Question 4.
Assertion: The refractive index of a prism depends only on the material of the prism.
Reason: The refractive index of a prism depends upon the refracting angle and angel of minimum deviation.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(c) If Assertion is true but Reason is false.

Question 5.
Assertion: A single lens produces a coloured image of an object illuminated by white light.
Reason: The refractive index of material of lens is different for different wavelength of light.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.

Question 6.
Assertion: If a convex lens is placed in water, its convergence power decrease.
Reason: Focal length of lens is independent of refractive index of the medium.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(c) If Assertion is true but Reason is false.

Question 7.
Assertion: Light waves travel in straight lines.
Reason: Rectilinear propagation of light confirm the above mentioned properly.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.

Question 8.
Assertion: Raman scattering the scattering of monochromatic light by atoms and molecule of a liquid.
Reason: The wavelength of Raman lines is same.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

Question 9.
Assertion: Power of a lens is the reciprocal of its focal length.
Reason: The unit of power is one dioptre when the unit of focal length is one metre.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.

Question 10.
Assertion: Presbyopia is due to ageing of human beings.
Reason: For those persons, ciliary muscles of the eye become weak.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If Assertion is false but Reason is true.
Answer:
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.

VI. Answer Briefly.

Question 1.
What is meant by refraction?
Answer:
When a ray of light travels from one transparent medium into another obliquely, the path of the light undergoes deviation. This deviation of ray of light is called refraction.

Question 2.
State laws of refraction.
Answer:
First law of refraction: The incident ray, the refracted ray of light and the normal to the refracting surface all lie in the same plane.

Second law of refraction: The ratio of the sine of the angle of incidence and sine of the angle of refraction is equal to the ratio of refractive indices of the two media. This law is also known as Snell’s law.
\(\frac{sin i}{sin r}\) = \(\frac{µ_2}{µ_1}\)

Question 3.
Define refractive index of a medium.
Answer:
The ratio of speed of light in vacuum to the speed of light in a medium is defined as refractive index ‘p’ of that medium.

Question 4.
What is meant by monochromatic source?
Answer:
If a source of light produces a light of single colour, it is known as a monochromatic source.

Question 5.
When white light is refracted by a transparent medium what will you get? Why?
Answer:

1. When white light is refracted by a transparent medium, a spectrum is obtained.
2. This is because, different coloured lights are bent through different angles.

Question 6.
What is scattering of light?
Answer:
When sunlight enters the Earth’s atmosphere, the atoms and molecules of different gases present in the atmosphere refract the light in all possible directions. This is called as ‘Scattering of light’.

Question 7.
State the types of scattering.
Answer:

1. Elastic scattering
2. Inelastic scattering

Question 8.
What is elastic scattering?
Answer:
If the energy of the incident beam of light and the scattered beam of light are same, then it is called as ‘elastic scattering’.

Question 9.
What is inelastic scattering?
Answer:
If the energy of the incident beam of light and the scattered beam of light are not same, then it is called as ‘inelastic scattering’.

Question 10.
How are different types of scattering formed? Mention the types of scattering.
Answer:
The nature and size of the scatterer results in different types of scattering. They are

1. Rayleigh scattering
2. Mie scattering
3. Tyndall scattering
4. Raman scattering

Question 11.
What is Rayleigh scattering?
Answer:
The scattering of sunlight by the atoms or molecules of the gases in the earth’s atmosphere is known as Rayleigh scattering.

Question 12.
Why the colour of the Sun is red at sunrise and sunset?
Answer:
At sunrise and sunset, the light rays from the Sun have to travel a larger distance in the atmosphere than at noon. Hence, most of the blue lights are scattered away and only the red light which gets least scattered reaches us. Therefore, the colour of the Sun is red at sunrise and sunset.

Question 13.
When does Mie scattering take place?
Answer:
Mie scattering takes place when the diameter of the scatterer is similar to or larger than the wavelength of the incident light.

Question 14.
What are the causes of Mie scattering?
Answer:
Mie scattering is caused by pollen, dust, smoke, water droplets, and other particles in the lower portion of the atmosphere.

Question 15.
Why the clouds have white appearance?
Answer:
Mie scattering is responsible for the white appearance of the clouds. When white light falls on the water drop, all the colours are equally scattered which together form the white light.

Question 16.
What is Tyndall Scattering?
Answer:
The scattering of light rays by the colloidal particles in the colloidal solution is called Tyndall Scattering or Tyndall Effect.

Question 17.
What is meant by colloid? State few examples.
Answer:
Colloid is a microscopically small substance that is equally dispersed throughout another material. Eg: Milk, Ice cream, muddy water, smoke.

Question 18.
What is meant by Raman Scattering?
Answer:
When a parallel beam of monochromatic (single coloured) light passes through a gas or liquid or transparent solid, a part of light rays are scattered.

Question 19.
Define Raman Scattering.
Answer:
Raman Scattering is defined as “The interaction of light ray with the particles of pure liquids or transparent solids, which leads to a change in wavelength or frequency.”

Question 20.
What is Rayleigh line?
Answer:
The spectral lines having frequency equal to the incident ray frequency is called ‘Rayleigh line’.

Question 21.
What are Raman lines?
Answer:
The spectral lines which are having frequencies other than the incident ray frequency are called ‘Raman lines’.

Question 22.
What are stokes lines and Antistokes lines?
Answer:
The lines having frequencies lower than the incident frequency is called stokes lines and the lines having frequencies higher than the incident frequency are called Antistokes lines.

Question 23.
What is a lens?
Answer:
A lens is an optically transparent medium bounded by two spherical refracting surfaces or one plane and one spherical surface.

Question 24.
How is lens classified?
Answer:
Lens is basically classified into two types. They are:

1. Convex Lens
2. Concave Lens.

Question 25.
What is biconvex lens?
Answer:
Convex or bi-convex lens: It is a lens bounded by two spherical surfaces such that it is thicker at the centre than at the edges. A beam of light passing through it, is converged to a point. So, a convex lens is also called as converging lens.

Question 26.
What is meant by biconcave lens?
Answer:
Concave or bi-concave Lens: It is a lens bounded by two spherical surfaces such that it is thinner at the centre than at the edges. A parallel beam of light passing through it, is diverged or spread out. So, a concave lens is also called as diverging lens.

Question 27.
What are
(i) Plano-convex lens?
(ii) Plano-concave lens?
Answer:
(i) If one of the faces of a bi-convex lens is plane, it is known as a plano-convex lens.
(ii) If one of the faces of a bi-concave lens is plane, it is known as a plano-concave lens.

Question 28.
State the applications of convex lenses.
Answer:

1. Convex lenses are used as camera lenses.
2. They are used as magnifying lenses.
3. They are used in making microscope, telescope and slide projectors.
4. They are used to correct the defect of vision called hypermetropia.

Question 29.
Draw diagrams of different types converging lenses.
Answer:

Question 30.
Represent different types of lenses by diagram.
Answer:

Question 31.
What is the nature of the image formed by an object is placed behind the centre of curvature of a convex leas. Draw a ray diagram.
Answer:
When an object is placed behind the center of curvature (beyond C), a real and inverted image is formed between the center of curvature and the principal focus. The size of the image is the same as that of the object.

Question 32.
Draw a ray diagram to indicate the nature of the image formed when an object is placed in between the centre of curvature and principal focus of a convex lens.
Answer:
When an object is placed in between the center of curvature and principal focus, a real and inverted image is formed behind the center of curvature. The size of the image is bigger than that of the object.

Question 33.
Draw a ray diagram for the formation of image (by the concave lens) when object is at infinity.
Answer:
When an object is placed at infinity, a virtual image is formed at the focus. The size of the image is much smaller than that of the object.

Question 34.
What are the applications of concave lens?
Answer:

1. Concave lenses are used as eye lens of‘Galilean Telescope’.
2. They are used in wide angle spy hole in doors.
3. They are used to correct the defect of vision called ‘myopia’.

Question 35.
What do you know about lens formula?
Answer:
The lens formula gives the relationship among distance of the object (u), distance of the image (v) and the focal length (f) of the lens. It is expressed as
\(\frac{1}{f}\) = \(\frac{1}{v}\) – \(\frac{1}{u}\)

Question 36.
Define magnification.
Answer:
It is defined as the ratio of the height of the image to the height of an object. Magnification is denoted by the letter ‘m’. If height of the object is h and height of the image is h’, the magnification produced by lens is,

Question 37.
What is lens formula?
Answer:
The lens formula relates the focal length of a lens with the distance of object and image.

where µ is the refractive index of the material of the lens; R₁ and R₂ are the radii of curvature of the two faces of the lens; f is the focal length of the lens.

Question 38.
What is meant by power of lens?
Answer:
The ability of a lens to converge (convex lens) or diverge (concave lens) light rays is called as its power.

Question 39.
Define power of a lens. State its unit.
Answer:
Power of a lens is numerically defined as the reciprocal of its focal length.
P = \(\frac{1}{f}\)
The SI unit of power of a lens is dioptre.

Question 40.
What is meant by dioptre.
Answer:
Dioptre is the power of a lens, whose focal length is 1 metre.
1 Dioptre = 1 m^-1.

Question 41.
Differentiate convex lens from concave lens.
Answer:

Question 42.
What are
(i) Pupil &
(ii) Retina?
Answer:
(i) Pupil: It is the centre part of the Iris. It is the pathway for the light to retina.
(ii) Retina: This is the back surface of the eye. It is the most sensitive part of human eye, on which real and inverted image of objects is formed.

Question 43.
What is persistence of vision?
Answer:
If the time interval between two consecutive light pulses is less than 0.1 second, human eye cannot distinguish them separately. It is called persistence of vision.

Question 44.
What is least distance of distinct vision?
Answer:
The minimum distance required to see the objects distinctly without strain is called least distance of distinct vision. It is called as near point of eye. It is 25 cm for normal human eye.

Question 45.
What is far point?
Answer:
The maximum distance up to which the eye can see objects clearly is called as far point of the eye.

Question 46.
What is Presbyopia?
Answer:
Due to ageing, ciliary muscles become weak and the eye-lens become rigid (inflexible) and so the eye loses its power of accommodation. Because of this, an aged person cannot see the nearby objects clearly. So, it is also called as ‘old age hypermetropia’.

Question 47.
What is meant by astigmatism?
Answer:
In this defect, eye cannot see parallel and horizontal lines clearly. It may be inherited or acquired. It is due to the imperfect structure of eye lens because of the development of cataract on the lens, ulceration of cornea, injury to the . refracting surfaces, etc. Astigmatism can be corrected by using cylindrical lenses (Torrid lenses).

Question 48.
State the principle of microscope. How is it classified?
Answer:
It works under the principle of angular magnification of lenses. It is classified as

1. Simple microscope
2. Compound microscope

Question 49.
What are the uses of simple microscope?
Answer:
Simple microscopes are used

1. By watch repairers and jewellers.
2. To read small letters clearly.
3. To observe parts of flower, insects etc.
4. To observe finger prints in the field of forensic science.

Question 50.
How is telescope classified?
Answer:
According to optical property, it is classified into two groups:

1. refracting telescope
2. reflecting telescope

Question 51.
Mention the advantages of telescope.
Answer:

1. Elaborate view of the Galaxies, Planets, stars and other heavenly bodies is possible.
2. Camera can be attached for taking photograph for the celestial objects.
3. Telescope can be viewed even with the low intensity of light.

Question 52.
What are the disadvantages of telescope?
Answer:

1. Frequent maintenance is needed.
2. It is not easily portable.

VII. Give the answer in Detail.

Question 1.
State the Laws of Refraction.
Answer:
The incident ray, the refracted ray of light and the normal to the refracting surface all lie in the same plane.
Second law of Refraction:

1. The ratio of the sine of the angle of incidence and sine of the angle of refraction is equal to the ratio of refractive indices of the two media. This law is also known as Snell’s law.
   \(\frac{\sin i}{\sin r}=\frac{\mu_{2}}{\mu_{1}}\)
2. Refractive index gives us an idea of how fast or how slow light travels in a medium. The ratio of the speed of light in a vacuum to the speed of light in a medium is defined as the refractive index ‘µ’ of that medium.
3. The speed of light in a medium is low if the refractive index of the medium is high and vice versa.
4. When light travels from a denser medium into a rarer medium, the refracted ray is bent away from the normal drawn to the interface.
5. When light travels from a rarer medium into a denser medium, the refracted ray is bent towards the normal drawn to the interface.

Question 2.
Describe Raman Scattering.
Answer:
When a parallel beam of monochromatic (single coloured) light passes through a gas or liquid or transparent solid, a part of light rays are scattered.

The scattered light contains some additional frequencies (or wavelengths) other than that of incident frequency (or wavelength). This is known as Raman scattering or Raman Effect.

Raman Scattering is defined as “The interaction of light ray with the particles of pure liquids or transparent solids, which leads to a change in wavelength or frequency.”

The spectral lines having frequency equal to the incident ray frequency is called ‘Rayleigh line’ and the spectral lines which are having frequencies other than the incident ray frequency are called ‘Raman lines’. The lines having frequencies lower than the incident frequency is called stokes lines and the lines having frequencies higher than the incident frequency are called Antistokes lines.

Question 3.
With the help of ray diagram, explain the nature, size and position of the image formed by a convex lens. When object is placed at
(i) infinity
(ii) beyond C
(iii) placed at C
(iv) Placed between F and C,
(v) placed at F
(vi) placed between F and optical centre O.
Answer:
(i) Object at infinity: When an object is placed at infinity, a real image is formed at the principal focus. The size of the image is much smaller than that of the object.

(ii) Object placed beyond C (>2F): When an object is placed behind the center of curvature(beyond C), a real and inverted image is formed between the center of curvature and the principal focus. Th e size of the image is the same as that of the object.

(iii) Object placed at C: When an object is placed at the center of curvature, a real and inverted image is formed at the other center of curvature. The size of the image is the same as that of the object.

(iv) Object placed between F and C: When an object is placed in between the center of curvature and principal focus, a real and inverted image is formed behind the center of curvature. The size of the image is bigger than that of the object.

(v) Object placed at the principal focus F: When an object is placed at the focus, a real image is formed at infinity. The size of the image is much larger than that of the object.

(vi) Object placed between the principal focus F and optical centre O: When an object is placed in between principal focus and optical centre, a virtual image is formed. The size of the image is larger than that of the object.

Question 4.
Explain the formation of images formed by a concave lens.
Answer:
Object at Infinity: When an object is placed at infinity, a virtual image is formed at the focus. The size of the image is much smaller than that of the object.

Object anywhere on the principal axis at a finite distance: When an object is placed at a finite distance from the lens, a virtual image is formed between optical center and focus of the concave lens. The size of the image is smaller than that of the object.

But, as the distance between the object and the lens is decreased, the distance between the image and the lens also keeps decreasing. Further, the size of the image formed increases as the distance between the object and the lens is decreased.

Question 5.
Explain Mie Scattering.
Answer:
Mie scattering:

1. Mie scattering takes place when the diameter of the Scatterer is similar to or larger than the wavelength of the incident light. It is also an elastic scattering.
2. The amount of scattering is independent of wavelength.
3. Mie scattering is caused by pollen, dust, smoke, water droplets, and other particles in the lower portion of the atmosphere.
4. Mie scattering is responsible for the white appearance of the clouds.
5. When white light falls on the water drop, all the colours are equally scattered which, together form the white light.

Question 6.
With the help of a diagram, explain the structure and working of human eye.
Answer:
Structure of the eye:
The eye ball is approximately spherical in shape with a diameter of about 2.3 cm. It consists of a tough membrane called sclera, which protects the internal parts of the eye.

Cornea : This is the thin and transparent layer on the front surface of the eyeball as shown in figure. It is the main refracting surface. When light enters through the cornea, it refracts or bends the light on to the lens.

Iris : It is the coloured part of the eye. It may be blue, brown or green in colour. Every person has a unique colour, pattern and texture. Iris controls amount of light entering into the pupil like camera aperture.

Pupil : It is the centre part of the Iris. It is the pathway for the light to retina.

Retina : This is the back surface of the eye. It is the most sensitive part of human eye, on which real and inverted image of objects is formed.

Ciliary muscles : Eye lens is fixed between the ciliary muscles. It helps to change the focal length of the eye lens according to the position of the object.

Eye Lens : It is the important part of human eye. It is convex in nature.

Working of the eye : The transparent layer cornea bends the light rays through pupil located at the centre part of the Iris. The adjusted light passes through the eye lens. Eye lens is convex in nature. So, the light rays from the objects are converged and a real and inverted image is formed on retina. Then, retina passes the received real and inverted image to the brain through optical nerves. Finally, the brain senses it as erect image.

Question 7.
Describe simple microscope.
Answer:
Simple microscope: It has a convex lens of short focal length. It is held near the eye to get enlarged image of small objects.
Let an object (AB) is placed at a point within the principal focus (u < f) of the convex lens and the observer’s eye is placed just behind the lens. As per this position the convex lens produces an erect, virtual and enlarged image (A’B’), The image formed is in the same side of the object and the distance equal to the least distance of distinct vision (D) (For normal human eye D = 25 cm).

Question 8.
Write short notes on
(i) Astronomical telescope
(ii) Terrestrial telescope.
Answer:
(i) Astronomical Telescope: An astronomical telescope is used to view heavenly bodies like stars, planets, galaxies and satellites.

(ii) Terrestrial Telescope: The image in an astronomical telescope is inverted. So, it is not suitable for viewing objects on the surface of the Earth. Therefore, a terrestrial telescope is used. It provides an erect image. The major difference between astronomical and terrestrial telescope is erecting the final image with respect to the object.

VIII. Numerical Problems.

Question 1.
A needle of size 5 cm is placed 45 cm from a lens produced an image on a screen placed 90 cm away from the lens.
Answer:
(i) Identify the types of lens.
Calculate focal length of the lens.
Height of the object h₁ = 5 cm
Distance of the object u = -45 cm
Distance of the image v = 90 cm
We know that

Focal length of the lens = 30 cm
Since focal length is positive the lens is convex lens.

(ii) Identify the size of the image

∴ h₂ = -10 cm
The negative sign indicates that the image is real and inverted.

Question 2.
A concave lens has focal length of 15 cm. At what distance should the object from the lens be placed so that it forms an image 10 cm from the lens?
Answer:
v = -10 cm; f =-15 cm; u = ?
Lens formula:
\(\frac{1}{f}\) = \(\frac{1}{v}\) – \(\frac{1}{u}\)
Type of lens: Concave lens

u =-30 cm
Thus, the object distance is 30 cm.

Question 3.
An object is placed at a distance of 30 cm from a concave lens of focal length 15 cm. An erect and virtual image is formed at a distance of 10 cm from the lens. Calculate the magnification.
Answer:
Type of lens is Cancave lens.
Formula:
Magnification m = \(\frac{v}{u}\)
Object distance u = -30 cm
Image distance v = -10 cm
m = \(\frac{-10}{-30}\) = \(\frac{1}{3}\) = +0.33

Question 4.
The focal length of a concave lens is 2 cm. Calculate the power of the lens.
Answer:
Formula:
P = \(\frac{1}{f}\)
Type of lens is concave lens.
Focal length of concave lens,
f = -2 m power of the lens.
P = \(\frac{1}{-2 m}\)
P = -0.5 dioptre

Question 5.
A needle placed at 30 cm from the lens forms an image on a screen placed 60 cm on the other side of the lens. Identify the type of lens and determine the focal length.
Answer:
u = -30 cm
v = 60 cm
u is negative because image is formed on the on the other side of the lens.

It is a convex lens.

Question 6.
A 3 cm tall bulb is placed at a distance of 20 cm from a diverging lens having a focal length of 10.5 cm. Determine the distance of the image.
Answer:
u = -20 cm
f = -10.5 cm

The distance of the image is -6.88 cm

Question 7.
A ray from medium 1 is refracted below while passing through medium 2. Find the refractive index of the second medium with respect to medium 1.
Answer:
Refractive index µ

Refractive index = 0.707

Question 8.
The optical prescription of a pair of spectacle is
Right eye: -3.5 D, Left eye: -4.00 D.
(i) Name the defect of the eye.
Answer:
Shortsighted (Myopia)

(ii) Are these lenses thinner at the middle or at the edges?
Answer:
These lenses are thinner in the middle.

(iii) Which lens has a greater focal length?
Answer:
power = \(\frac{1}{focal length}\)
Right eye: power P = -3.5 D

Left eye: Power P = -4 D

Hence the lens having power of -3.5 D has greater focal length.

Question 9.
The radii of curvature of two surfaces of a double convex lens are 10 cm each. Calculate its focal length and power of the lens in air and liquid. Refractive indices of glass and liquid are 1.5 and 1.8 respectively.
Answer:
Radius of curvature of first surface R₁ = 10 cm
Radius of curvature of second surface R₂ = 10 cm
In air

p_l = -3.33 d

Question 10.
An object 2 cm tall is placed 10 cm in front of a convex lens of focal length 15 cm. Find the position, size and nature of the image formed.
Answer:
Focal length of a convex lens f = 15 × 10^-2 m
Weight of the object ho = 2 × 10^-2 m
Let weight of the image be h_v
Distance of the object u = 10 × 10^-2 m
Distance of the image v = 15 × 10^-2 m
We know

∴ v = -30 × 10^-2 m
Distance of the image = 30 × 10^-2 m

Hence a virtual image 6 × 10^-2 m height is formed at a distance of 30 × 10^-2 m from the lens on the same side of the lens.

IX. Higher order thinking (HOT) questions.

Question 1.
Ramu passes white light through a quartz prism. For which colour refractive index is greater?
Answer:
Refractive index is maximum for violet light when white light passes through a quartz prism.

Question 2.
Sita has kept a stud consists of diamond. What will she observe? Give reason.
Answer:
The diamond stud appears bright because of total internal reflection.

Question 3.
Guna passes a ray light through a glass slab. Which optical phenomenon will take place? What can he observe with reference to wavelength?
Answer:
When a ray of light enters a glass slab he can observe refraction of light. He observed that wavelength of light decreases.

Question 4.
A prism is placed in the minimum deviation position. Chari has passed a ray of light at an angle of 45°, then what is the value of angle of emergence? Why?
Answer:
The angle of emergence = 45°.
Since, in the minimum deviation positron, angle of incidence is equal to angle of emergence.

Question 5.
Mani is using a lens of power 2 dioptre. What is the focal length of the lens?
Answer:
Focal length = \(\frac{1}{power}\)
F= \(\frac{1}{2}\) = 0.5 m

Question 6.
Surya has placed a lens of power 1 D in side water. What will happen to power of the lens?
Answer:
The power of the lens will be more than original power.

Question 7.
Sonu has observed some lines in solar spectrum are absorbed by the elements present in the atmosphere. What are the lines?
Answer:
The lines are Fraunhofer lines.

Students can download 10th Social Science History Chapter 3 World War II Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions History Chapter 3 World War II

Samacheer Kalvi 10th Social Science World War II Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
When did the Japanese formally sign of their surrender?
(a) 2 September, 1945
(b) 2 October, 1945
(c) 15 August, 1945
(d) 12 October, 1945
Answer:
(a) 2 September, 1945

Question 2.
Who initiated the formation of League of Nations?
(a) Roosevelt
(b) Chamberlain
(c) Woodrow Wilson
(d) Baldwin
Answer:
(a) Roosevelt

Question 3.
Where was the Japanese Navy defeated by the US Navy?
(a) Battle of Guadalcanal
(b) Battle of Midway
(c) Battle of Leningrad
(d) Battle of El Alamein
Answer:
(b) Battle of Midway

Question 4.
Where did the US drop its first atomic bomb?
(a) Kavashaki
(b) Innoshima
(c) Hiroshima
(d) Nagasaki
Answer:
(c) Hiroshima

Question 5.
Who were mainly persecuted by Hitler?
(a) Russians
(b) Arabs
(c) Turks
(d) Jews
Answer:
(d) Jews

Question 6.
Which Prime Minister of England who signed the Munich Pact with Germany?
(a) Chamberlain
(b) Winston Churchill
(c) Lloyd George
(d) Stanley Baldwin
Answer:
(a) Chamberlain

Question 7.
When was the Charter of the UN signed?
(a) June 26, 1942
(b) June 26, 1945
(c) January 1, 1942
(d) January 1, 1945
Answer:
(b) June 26, 1945

Question 8.
Where is the headquarters of the International Court of Justice located?
(a) New York
(b) Chicago
(c) London
(d) The Hague
Answer:
(d) The Hague

II. Fill in the blanks

1. Hitler attacked ……………… which was a demilitarized zone.
2. The alliance between Italy, Germany and Japan is known as ………………
3. ……………… started the Lend-Lease programme.
4. Britain Prime Minister ……………… resigned in 1940.
5. Saluting the bravery of the ……………… Churchill said that “Never was so much owed by so many to so few”.
6. ……………… is a device used to find out the enemy aircraft from a distance.
7. The Universal Declaration of Human Rights set forth fundamental human rights in ……………… articles.
8. After the World War II ……………… was voted into power in Great Britain.

Answers:

1. Rhineland
2. Rome – Berlin
3. Roosevelt
4. Chamberlain
5. Royal Air force
6. Radar
7. 30
8. Labour party

III. Choose the correct statement

Question 1.
(i) Banking was a major business activity among Jews.
(ii) Hitler persecuted the Jews.
(iii) In the concentration camps Jews were killed.
(iv) The United Nations has currently 129 member countries in it.
(a) (i) and (ii) are correct
(b) (i) and (Hi) are correct
(c) (iii) and (iv) are correct
(d) (i) is correct and (ii), (iii) and (iv) are wrong
Answer:
(a) (i) and (ii) are correct

Question 2.
Assertion (A): President Roosevelt realised that the United States had to change its policy of isolation.
Reason (R): He started a programme of Lend Lease in 1941.
(a) Both A and R are correct
(b) A is right but R is not the correct reason
(c) Both A and R are wrong
(d) R is right but it has no relevance to A
Answer:
(a) Both A and R are correct

IV. Match the Following

Answers:
A. (v)
B. (iv)
C. (i)
D. (ii)
E. (iii)

V. Answer the questions briefly

Question 1.
Mention the important clauses of the Treaty of Versailles relating to Germany.
Answer:

1. Germany was forced to give up territories to the west, north and east of the German border.
2. Germany had to be disarmed and was allowed to retain only a very restricted army, navy and air force.
3. Germany was expected to pay huge military and civilian cost of the war to the allied nations (approx. $ 25 billion).

Question 2.
Who were the three prominent dictators of the post World War I?
Answer:
The three prominent dictators of the post-World War I were Mussolini (Italy), Hitler (Germany) and Franco (Spain).

Question 3.
How did Hitler get the support from the people of Germany?
Answer:
Hitler was able to sway away the emotions of the German people by his great speeches. He promised them that he will return back the glorious Germany. His racial superiority of the Germans as a pure Aryan race and a deep-rooted hatred for jews made him get the support of his people.

Question 4.
Describe the Pearl Harbour incident.
Answer:
Pearl Harbour incident took place in December 1941 when japan attacked American naval installations in Pearl Harbour, Hawaii, without warning to cripple America’s Pacific fleet. Many battle ships and numerous fighter planes were destroyed. The US declared war on Japan, with Britain and China. This brought together both the Asia Pacific and the European war into one common cause. Most importantly, it brought the United States with its enormous resources into the war as a part of the Allies.

Question 5.
What do you know of Beveridge Report?
Answer:
The Report that was published in the United Kingdom in 1942 to improve the general welfare of the people is called as Beveridge Report. It proposed that the government should provide citizens with adequate income, healthcare, education housing and employment to overcome poverty and disease thereby improve general welfare.

Question 6.
Name the Bretton Woods Twins.
Answer:
The World Bank and the International Monetary Fund.

Question 7.
What are the objectives of the IMF?
Answer:

1. To foster global monetary co-operation
2. To secure Financial Stability
3. To facilitate International Trade
4. To promote high employment and sustainable economic growth.
5. To reduce poverty around the world.

VI. Answer the questions given under each caption

Question 1.
Battle of Stalingrad

(a) When did Germany attack Stalingrad?
Answer:
In August 1942, Germany attacked Stalingrad.

(b) What were the main manufactures of Stalingrad?
Answer:
The main manufactures of Stalingrad were armaments and tractors.

(c) What was the name of the plan formulated by Hitler to attack Stalingrad?
Answer:
Fall Blau or Operation Blue

(d) What is the significance of the Battle of Stalingrad?
Answer:
The people of Russia were grateful for Stalin’s conduct of the war. They regarded him as ‘a prodigy of patience, tenacity and vigilance, almost omnipresent, almost omniscient.

Question 2.
Japanese Aggression In South-east Asia

(a) Name the South-east Asian countries which fell to the Japanese.
Answer:
Guam, the Philippines, Hong Kong, Singapore, Malaya, the Dutch East Indies and the Burma all fell to the Japanese.

(b) Account for the setback of Allies in the Pacific region?
Answer:
The Allies had a setback in the Pacific region because of their inadequate preparation. The local people had to face the atrocities of the Japanese.

(c) What is the significance of Battle of Midway?
Answer:
The U.S. navy defeated the Japanese navy in the Battle of Midway. Thus, the battle is in favour of the Allies.

(d) What happened to the Indians living in Burma?
Answer:
The Indians living in Burma walked all the way to the Indian border facing many hardships. Many died of disease and exhaustion.

Question 3.
General Assembly and Security Council

(a) List the permanent member countries of the Security Council.
Answer:
The United States, Britain, France, Russia and China.

(b) What is the Holocaust?
Answer:
The word ‘holocaust’ is used to describe the genocide of nearly six million Jews by the Germans during the Second World War.

(c) Who was the Chairperson of the UN Commission on Human Rights?
Answer:
The widow of US President Franklin Roosevelt was the chairperson of the UN Commission on Human Rights.

(d) What is meant by veto?
Answer:
A veto is the power to unilaterally stop an official action, especially the enactment of legislation.

VII. Answer in detail

Question 1.
Attempt an essay on the rise and fall of Adolf Hitler.
Answer:

1. Adolf Hitler Was the founder of the National Socialist party, generally known as the Nazi party.
2. His great oratorical skill, his promise to bring back the glorious past of Germany, his support for the German race and hatred towards the Jews helped him to get people support.
3. He came to power in 1933 and ruled Germany till 1945.
4. He began to re-arm Germany and recruitment of new armed forces.
5. The manufacture of armaments and machinery for the army, navy and air force with large spending from government resulted in the revival of the economic condition and helped to solve the unemployment problem in the economy.
6. He followed aggressive policy and therefore in 1936, he invaded Rhine land, the demilitarized zone.
7. His alliance with Italy and Japan became Rome-Berlin-Tokyo axis.
8. He signed Munich pact stating Germany would not conquer any other territory, rather in 1939, he invaded Czechoslovakia.
9. His attack on Poland resulted in the declaration of war by Britain and France against Germany.
10. In 1941, German army invaded Russia. But the resistance of the German army and Russian winter defeated German army.
11. When the allied forces fought back, Germany also retaliated. Finally, Hitler committed suicide in 1945.
12. In 1945, allies occupied Berlin and Germany was divided as two sections after the war.

Question 2.
Analyse the effects of World War II.
Answer:
World War II was the most devastating war in history. It left a deep impact on the entire world. It changed the world in fundamental ways. Here are the effects of this War:

(i) The world got polarised into two main blocs led by superpowers, one led by the United States which followed anti-communist ideology, and the other by Soviet Russia which was essentially communist in nature. Europe was thus divided into two: Communist and non-communist.

(ii) The United States and the Soviet Union entered into a race to have more nuclear powered World War II 43 weapons. They built a large stockpile of such weapons. Meanwhile, Britain and France developed their own nuclear weapons.

(iii) Gradually there arose competition among countries. They began to devote large amount of resources in developing more and more powerful weapons with great destructive power, and defence spending skyrocketed in many countries.

(iv) It was realised that the League of Nations was ineffective and weak. So countries of the world decided not to repeat the mistake. Instead, many international agencies, in particular the United Nations, the World Bank and the International Monetary Fund came into existence providing a forum for countries large and small.

(v) Many other important social and economic changes also took place in the post-War world. Colonial powers were forced to give independence to former colonies in a process of decolonisation. India was the first country to get independence.

(vi) Women became the part of labour force in huge numbers. They became economically independent.

Question 3.
Assess the structure and activities of the UN.
Answer:
The charter of the United Nations was signed on June 26, 1945 by 51 nations. Now, the United Nations has 193 member states and each one has an equal vote in the UN.

Structure of UN:

The General Assembly: Meets once in a year. Issues of interest and points of conflict are discussed in the Assembly.

The Security Council: Consist of five permanent members (USA, Britain, France, Russia, China) and ten non-permanent members (elected in rotation). Each permanent member has the right to veto (A right to reject a decision).

UN Secretariat: Headed by the Secretary by law General. He is elected by the General Assembly on the recommendations of the Security Council. He, with his cabinet and officials run the UN.

International Court of Justice: Headquarters at the Hague in Holland.

The Economic and the Social Council: Co-ordinates all the social and economic work of the U.N. Headed by economists like Gunnar Myrdal.

Activities of the UN:

1. Human Rights, Refugees problem, climatic change, gender equality are the important issues taken over and deals with it. Earlier in 1960’s decolonisation was also a part of their activity.
2. UN peace keeping force acted in many areas of conflict all over the World. Indian army has been a part of it.
3. The preamble of the UN declares, its activities include human rights, equality of men and women.

VIII. Students Activity

Question 1.
A debate in the class on the success or failure of the UN in preserving World Peace.
Answer:
The students can take the following topics for debate and finally conclude, UN is successful as it has stopped the nations from bringing another war. Small to big clashes were/are handled by UN efficiently.

Argument for:
The topics of discussion for debate are:

1. Solving International conflicts: Since 1945, UN peacekeepers have undertaken over 60 field missions and negotiated 172 peaceful settlements that ended Regional conflicts.
2. Liberation from Colonial rule: Eighty nations and more than 750 million people have been freed from colonialism.
3. Human Rights: Custodian for the protection of human rights, discrimination against women, Children’s rights, torture, missing persons etc. in many countries.
4. Enhancing Human life: Specialised agencies of the UN engaged in enhancing all aspects of human life, including education, health, poverty reduction, climate change.
5. Treaties: More than 560 multilateral treaties on human rights, refugees, disarmament.

Argument against:

Non-proliferation Treaty (NPT): Signed by 190 nations, all live superpowers owned nuclear weapons. Later, several countries North Korea, Israel, Pakistan, India developed nuclear weapons.

Veto Power: Veto power has limited its effectiveness at critical times.

War Criminals: The International criminal court has prosecuted several war criminals. But it has been criticised for prosecuting only African leaders. But Western powers too have committed war crimes.

Israel Attack: Israel attacked homes schools, U.N. shelters in Gaza killing 2,200 Palestinians. The U.N. Security Council has failed any action against Israel.

Conclusion: U.N. is imperfect but it is also indispensable. It is successful as, it is avoiding any other war.

Question 3.
Marking the Allies and Axis countries, as well as important battlefields of World War II in a world map.
Answer:

IX. Map Work

Question 1.
Mark the following on the world map.
1. Axis Power Countries
2. Allied Power Countries
3. Hiroshima, Nagasaki, Hawai Island, Moscow, San Fransico
Answer:
(2)

(3)

Timeline:

Samacheer Kalvi 10th Social Science World War II Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
The financial cost of the II World War was ……………….. times higher than that of the I World War.
(a) one
(b) three
(c) five
(d) seven
Answer:
(c) five

Question 2.
The coal mines given to France were ………
(a) Jharia
(b) Saar
(c) Bokaro
Answer:
(b) Saar

Question 3.
“Money in wheelbarrows to buy bread” in the 1920’s. Which country referred to here.
(a) Italy
(b) Austria
(c) Germany
(d) Spain
Answer:
(c) Germany

Question 4.
The principles of war and conquests was glorified by ………
(a) Moderates
(b) Dictators
(c) Extremists
Answer:
(b) Dictators

Question 5.
Hitler broke the Munich pact by invading ……………….. in 1939.
(a) Manchuria
(b) Sudetenland
(c) Poland
(d) Czechoslovakia
Answer:
(d) Czechoslovakia

Question 6.
Hitler demanded the surrender of ………
(a) Danzig
(b) Jutland
(c) Estonia
Answer:
(a) Danzig

Question 7.
The attack of ……………….. by Germany was the final act which result in the initiation of II World War.
(a) Britain
(b) France
(c) Russia
(d) Poland
Answer:
(d) Poland

Question 8.
The British Prime Minister during the Second World War was ………
(a) Sir Winston Churchill
(b) Clement Atlee
(c) Lloyd George
Answer:
(a) Sir Winston Churchill

Question 9.
The tactic followed by Germany to overrun other countries was called as:
(a) Sea-borne invasion
(b) Blitzkrieg
(c) Dunkirk
(d) None
Answer:
(b) Blitzkrieg

Question 10.
In ………, Hitler invaded Russia.
(a) 1940
(b) 1941
(c) 1943
Answer:
(b) 1941

Question 11.
“We shall fight in the fields and in the streets” ……………….. but, we shall never surrender.”- said by
(a) Winston Churchill
(b) Napoleon Bonaparte
(c) George Washington
(d) Roosevelt.
Answer:
(a) Winston Churchill

Question 12.
……………….. used the device radar for detecting aircraft at a distance in World War II.
(a) Germany
(b) Japan
(c) Britain
(d) USA
Answer:
(c) Britain

Question 13.
In September 1940, London was bombed mercilessly by German Air force. This action was called as:
(a) Spit fires
(b) Hurricanes
(c) Blitz
(d) Dunkirk
Answer:
(c) Blitz

Question 14.
Land lease programme of USA took place between the years:
(a) 1939 – 1945
(b) 1941 – 1945
(c) 1936 – 1940
(d) 1914 – 1918
Answer:
(b) 1941 – 1945

Question 15.
In the war between Germany and Russia in 1941, ……………….. was defeated.
(a) Germany
(b) Russia
(c) Britain
(d) None
Answer:
(a) Germany

Question 16.
Stalingrad I situated along the banks of the river:
(a) Miami
(b) Volga
(c) Hwang-Ho
(d) Marne
Answer:
(b) Volga

Question 17.
In the battle of Stalingrad, Germans used the code word ……………….. on Russia.
(a) Alamein
(b) Land lease
(c) Fall Blau
(d) Montegomary
Answer:
(c) Fall Blau

Question 18.
Mussolini was killed by a ……………….. partisan.
(a) Germany
(b) Italy
(c) Russia
(d) Britain
Answer:
(b) Italy

Question 19.
Mussolini was killed in:
(a) May 1945
(b) April 1944
(c) April 1945
(d) May 1946
Answer:
(c) April 1945

Question 20.
In 1945 ……………….. was divided into two sections.
(a) Germany
(b) Italy
(c) Bengal
(d) Russia
Answer:
(a) Germany

Question 21.
Japanese army indulged in the biggest slaughter in the place ……………….. in China.
(a) Manchuria
(b) Nanking
(c) Peking
(d) Shangai
Answer:
(b) Nanking

Question 22.
Japan announced surrendered to U.S on ……………….. 1945.
(a) 2nd September
(b) 15th August
(c) 3rd August
(d) 5th February
Answer:
(b) 15th August

Question 23.
The Security council has ……………….. members.
(a) 10
(b) 15
(c) 25
(d) 3
Answer:
(b) 15

Question 24.
At present, the United Nations has ……………….. member states.
(a) 196
(b) 195
(c) 194
(d) 193
Answer:
(d) 193

Question 25.
The World Bank is located at:
(a) Sweden
(b) New Zealand
(c) Washington
(d) New York
Answer:
(c) Washington

Question 26.
IMF has at present ……………….. member countries.
(a) 200
(b) 187
(c) 189
(d) 190
Answer:
(c) 189

Question 27.
IMF help the countries to solve their ……………….. position.
(a) debt
(b) Balance of payment
(c) Independency
(d) Trade
Answer:
(b) Balance of payment

Question 28.
The report published in 1942, in United Kingdom for the general welfare of the people was called as ……………….. report.
(a) Bretton Woods
(b) Beveridge
(c) Blitzkrieg
(d) Common wealth
Answer:
(b) Beveridge

Question 29.
……………….. party in Great Britain promised for a welfare state to the people.
(a) Communist party
(b) Democratic party
(c) Socialised party
(d) Labour party
Answer:
(d) Labour party

Question 30.
The benefits to the people can be achieved either through ……………….. transfers or free services.
(a) Cash
(b) Country
(c) State
(d) Regional
Answer:
(a) Cash

II. Fill in the blanks

1. World War II began in ……………… and ended in ………………
2. The Treaty of ……………… was signed at the end of World War I in 1919.
3. The Germans offered to pay ……………… billion gold marks to the allies.
4. The United States was faced with great depression after ………………
5. The National Socialist party in Germany was generally known as ………………
6. In 1938, Hitler signed the Munich pact with Prime Minister ………………
7. In 1939, Hitler invaded ……………… as against his promise in Munich pact.
8. Hitler showed hatred against ………………
9. Hitler came to power in ……………… and ruled till ………………
10. World War II was a ……………… war fought with tanks, submarines, bomber planes etc.
11. Britain and France declared war on Germany in ………………
12. In ………………, Italy and Japan joined the axis powers.
13. In September 1940, London war bombed by Germans mercilessly. This action was known as ………………
14. Blitzkrieg means ………………
15. The name of the Britain navy was ………………
16. The war between Britain and ……………… took place in Dunkirk in 1940.
17. The fighter planes of the British Royal force was called as ……………… and ………………
18. ……………… of America started the Land Lease programme.
19. Caucasus was famous for its ……………… in Russia.
20. Mussolini of Italy was killed by an ……………… partisan.
21. The battle of ……………… was considered to be the Great patriotic war by the Russians.
22. Italy surrendered to the allies in ………………
23. The Allied forces under the command of ……………… invaded Normanday in France.
24. Canton was called as ……………… in China.
25. On December 1941, ……………… attacked American naval installations in Pearl Harbour.
26. Guadalcanal is in the ……………… islands.
27. USA dropped an atomic bomb on ……………… and ……………… cities of Japan.
28. Japan announced their surrender on ………………
29. Japan formally signed their surrender marking the end of the World War II was ………………
30. ……………… and ……………… are the two super powers after the II World War.
31. US and Soviet Russia entered into a race to have more ………………
32. ………………, ………………, and ……………… came into existence after the II World War.
33. ……………… started entering into labour force in huge number after World War II.
34. In the process ofdecolonisation ……………… was the first country toget Independence.
35. The word ……………… refers the genocide of Jews by the Germans during Second World War.
36. A major outcome of the Holocaust was the creation of the State of ………………
37. ……………… became the Homeland for Jews after II World War.
38. The Un efforts to protect human rights at the global levei resulted in the UN commission on ………………
39. The Un adopted the Human Rights Charter on ………………
40. ……………… is observed globally as Human Rights Day.
41. Britain and United States gave a joint declaration called as ……………… in 1941 that helped in the formation of UNO.
42. ……………… were the axis powers of the II World War.
43. The initial member States of the UN were ……………… nations.
44. The Charter of the United Nations was signed on ………………
45. Each member State in U.N.has ……………… vote.
46. The UN functions almost like a ………………
47. There are ………………, ………………, ………………, ……………… wing for the UN.
48. Veto means ………………
49. ……………… has veto power.
50. ……………… permanent members are there in UN.
51. WHO means ………………
52. UNICEF means ………………
53. FAO means ………………
54. UNESCO expansion is ………………
55. UNDP expansion is ………………
56. The ……………… has been a port of peace keeping force of the UN in deployment to many parts of the World.
57. The World Bank and the IMP are referred to as ………………
58. The two main organs of the World Bank are ……………… and ………………
59. IBRD expansion is ………………
60. IDA expansion is ………………
61. The IDA lends money to the ……………… for development activities.
62. The loans sanctioned by IDA at low interest rates for development purposes are called as ………………
63. Soft loans are given for ……………… years.
64. The ……………… functions with private enterprises in developing countries.
65. IFC expansion is ………………
66. The World Bank is actively promoting the cause of improving the and eradicating the ………………
67. The IMF was the brainchild of ……………… and ………………
68. The initial member countries of IMF were ………………
69. Its primary objective is to ensure ……………… and development across the World.
70. The fund gives resources to countries facing ……………… problem.
71. The number of member countries of IMF at present are ……………… countries.
72. All the countries in the Western Europe are now ………………
73. The ……………… in Great Britain after World War I promised to look at the people from the cradle to the grave.
74. Legislations was enacted to provide comprehensive free health coverage to the citizens in Britain through ………………
75. The monetary benefits after World War II by Labour party was ………………, ……………… etc.

Answers:

1. 1939, 1945
2. Versailles
3. 100
4. 1929
5. Nazis
6. Chamberlin
7. Czechoslovakia
8. Jews
9. 1933, 1945
10. modem
11. 1939
12. 1940
13. Blitz
14. Lightning strike
15. Royal Navy
16. France
17. Spitfires, Hurricanes
18. President Roosevelt
19. Oil fields
20. Italian
21. Stalingrad
22. 1943
23. General Elsenhower
24. Guangzhou
25. Japan
26. Solomon
27. Hiroshima, Nagasaki
28. 15th August 1945
29. 2nd Sept 1945
30. United States, Soviet Russia
31. Nuclear weapons
32. United Nations, World Bank, International Monetary Fund
33. Women
34. India
35. Holocaust
36. Israel
37. Israel
38. Human Rights
39. 10th Dec 1948
40. 10th Dec 1948
41. Atlantic Charter
42. Germany, Italy, Japan
43. 51
44. June 26, 1945
45. One
46. Government
47. Executive, Judicial, Legislative, Co-ordinating
48. The right to block major decisions
49. Permanent members
50. Five
51. World Health Organisation
52. United Nations Children’s Fund
53. Food and Agricultural Organisation
54. UN educational, Scientific and Cultural Organisation
55. United Nations Development programme
56. Indian Army
57. Bretton Woods Twins
58. IBRD, IDA
59. International Bank for Reconstruction and Development
60. International Development Agency
61. Government
62. Soft loans
63. 50
64. IFC
65. International Finance Corporation
66. Environment, AIDS
67. Hary Dexter, John Maynard Keynes
68. 29
69. Financial Stability
70. Balance of payment
71. 189
72. Welfare states
73. Labour party
74. National Health Service
75. Old age pension, Child care services

III. Choose the correct statement

Question 1.
(i) The axis powers of World War II were Germany, Italy and Japan.
(ii) Russia attacked the American naval base at Pearl Harbour in 1941.
(iii) The UN adopted the historic human rights charter on 10th December 1947.
(iv) The executive wing of the UN is the UN Secretariat.
(a) (i) (ii) are correct
(b) (i) (ii) (iii) are correct
(c) (i) (iv) are correct
(d) (ii) (iv) are wrong.
Answer:
(c) (i) (iv) are correct

Question 2.
(i) Reparations refers to the compensation exacted from a defeated nation by the victorious nation.
(ii) Slaughter is compulsory military service.
(iii) Japanese navy was defeated by the US Navy at the battle of mid way.
(iv) Progression taxation by taxing the higher income groups at relatively high rates.
(a) (ii) (iii) (iv) are correct
(b) (ii) (iv) are wrong
(c) (iii) (iv) are correct
(d) (iii) (iv) are wrong.
Answer:
(a) (ii) (iii) (iv) are correct

Question 3.
(i) The Security Council of the UNO has fifteen members.
(ii) The mass killing of Jews in Nazi was called holocaust
(iii) Battle of Ex Alamein was considered one of the greatest battles by Russia.
(iv) The Japanese navy defeated the US navy in the battle of Midway.
(a) (i) (ii) are correct
(b) (ii) (iv) are correct
(c) (i) (ii) (iii) are correct
(d) (i) (iv) are wrong
Answer:
(a) (i) (ii) are correct

Question 4.
(i) The World Bank and the IMF are referred to as the Bretton Woods Twins.
(ii) The post World War I led to the rise of dictatorship in Italy, Germany, and Spain.
(iii) The post World War II changed the world into two blocks as communist and non communist.
(iv) The Shakespeare’s play the Merchant of Venice clearlv depicts the dislike and distrust of Jews among the Nazi people.
(a) (i) (ii) are correct
(b) (i) (ii) (iii) are wrong
(c) (i) (ii) (iii) (iv) are correct
(d) (iii) (iv) (ii) are wrong
Answer:
(c) (i) (ii) (iii) (iv) are correct

Question 5.
(i) IMF lends money from its resources to countries facing balance of payment problem.
(ii) The Munich pact was signed between Germany and the Soviet Union.
(iii) Huge worthless money for bread often refers to the Britain’s severe inflation after II World War.
(iv) Franco of Spain was the only dictatorship that emerged after II World War.
(a) (i) (ii) are correct
(b) (i) (iii) (iv) are correct
(c) (i) (ii) (iii) (iv) are wrong
(d) (i) (iv) are correct
Answer:
(a) (i) (ii) are correct

Question 6.
(i) Japanese extended their empire throughout South-east Asia.
(ii) Burma, Indonesia, Singapore, Malaya, Hong Kong, Philippines all fell to the Japanese.
(iii) Many Indians walked ail the way from Burma to the Indian border facing many sufferings.
(iv) Many Indians who stayed there suffered under the Japanese.
(a) (ii) (iv) are wrong
(b) (i) (ii) (iii) (iv) are correct
(c) (iii) (i) are correct
(d) (i) (ii) (iii) (iv) are wrong
Answer:
(b) (i) (ii) (iii) (iv) are correct

Question 7.
(i) Hitler was killed by his countrymen in 1945
(ii) Mussolini committed suicide in April 1945
(iii) The United States declared war on Japan on December 1944.
(iv) In 1938, Japan invaded China and seized Beijing.
(a) (ii) (iv) are wrong
(b) (i) (ii) (iii) (iv) are correct
(c) (i) (ii) are correct
(d) (i) (ii) (iii) (iv) are wrong
Answer:
(d) (i) (ii) (iii) (iv) are wrong

Question 8.
(i) In the year 1940, the British Prime Minister Chamberlain resigned.
(ii) The newly elected British Prime Minister next was Winston Churchill.
(iii) The end of World War II signalled a change in the world order and political configurations among the major powers.
(iv) The Treaty of Versailles ended the World War II.
(a) (i) (iv) are wrong
(b) (i) (ii) (iii) (iv) are correct
(c) (i) (ii) (iii) are correct
(d) (i) (ii) (iv) are correct
Answer:
(c) (i) (ii) (iii) are correct

IV. Assertion and Reason

Question 1.
Assertion (A): World War I (1914-18) and World War II (1939-45) are only referred as World wars.
Reason (R): The high death of the civilians and the soldiers and the extended area of the conflicts.
(a) Both A and R are correct
(b) A is correct but R is not the correct reason
(c) Both A and R are wrong
(d) R is correct but A is wrong.
Answer:
(a) Both A and R are correct

Question 2.
Assertion (A): The League remained an ineffectual international body. Reason (R): Along with the USA, as a non-member mainly Germany was determined to maintain a non-interventionist attitude.
(a) Both A and R are correct
(b) A is correct but R is not the correct reason
(c) Both A and R are wrong
(d) R is correct but A is wrong.
Answer:
(b) A is correct but R is not the correct reason

Question 3.
Assertion (A): Hitler invaded Austria and Czechoslovakia in 1938.
Reason (R): Hitler claimed all the German speaking people should be united into one nation.
(a) Both A and R are correct
(b) A is correct but R is not the correct reason
(c) Both A and R are wrong
(d) R is correct but A is not relevant to R.
Answer:
(a) Both A and R are correct

Question 4.
Assertion (A): The mood in Britain was not in favour of starting another war after World War I.
Reason (R): Just as the United States they wanted to be concerned with the revival of the economy after great depression.
(a) Both A and R are correct
(b) A is correct but R is not the correct reason
(c) Both A and R are wrong
(d) R is correct but A is not relevant to A.
Answer:
(b) A is correct but R is not the correct reason

Question 5.
Assertion (A): Germany developed a fleet of sub-marines which caused havoc in the Atlantic Ocean.
Reason (R): Germany ensured themselves for a sea-borne invasion on allies.
(a) Both A and R are correct
(b) A is right but R is not the correct explanation of A.
(c) Both A and R are wrong
(d) R is correct, which is not relevant to A.
Answer:
(b) A is right but R is not the correct explanation of A.

Question 6.
Assertion (A): The long term objective of Germany was to exploit Russia’s natural Resource oil.
Reason (R): German army invaded Russia.
(a) Both A and R are correct
(b) A is right but R is not the correct explanation of A
(c) Both A and R are wrong
(d) R is correct, which is not relevant to A.
Answer:
(a) Both A and R are correct

Question 7.
Assertion (A): Germans tried to capture the city of Stalingrad in Russia. Reason (R): Stalingrad was the militarised zone of Russia.
(a) Both A and R are correct
(b) A is right, but R is not the correct explanation of A
(c) Both A and R are wrong
(d) R is right, A is wrong.
Answer:
(b) A is right, but R is not the correct explanation of A

Question 8.
Assertion (A): Hitler committed suicide in April 1945.
Reason (R): The Allied forces in 1945, occupied parts of Berlin and began to attack Germany from the east.
(a) Both A and R are correct
(b) A is correct but R is not the correct explanation.
(c) Both A and R are wrong
(d) R is correct but A is not relevant to R.
Answer:
(a) Both A and R are correct

Question 9.
Assertion (A): The United States declared war on Japan.
Reason (R): In 1931, the Japanese army invaded Manchuria and in 1937, invaded China and seized Beijing.
(a) Both A and R are correct
(b) A is correct but R is not the correct explanation of A
(c) Both A and R are wrong
(d) R is correct but R is not relevant to A.
Answer:
(b) A is correct but R is not the correct explanation of A

Question 10.
Assertion (A): U.S. dropped an atomic bomb on Hiroshima and another bomb was dropped on Nagasaki.
Reason (R): U.S. developed hatred over the development of two cities Hiroshima and Nagasaki.
(a) Both A and R are correct
(b) A is correct, but R is not the correct explanation of A
(c) Both A and R are wrong
(d) R is correct but it is the correct reason for A.
Answer:
(b) A is correct, but R is not the correct explanation of A

Question 11.
Assertion (A): The U.S. and the Soviet Union followed communist and non¬communist ideas.
Reason (R): Countries began to devote large amount of resources in developing dangerous weapons.
(a) Both A and R are correct
(b) A is correct, but not relevant to R
(c) Both A and R are wrong
(d) R is correct, but not relevant to A.
Answer:
(c) Both A and R are wrong

V. Match the Following

Question 1.
Match the Column I with Column II.

Answer:
A. (iv)
B. (i)
C. (v)
D. (vi)
E. (iii)

Question 2.
Match the Column I with Column II.

Answer:
A. (v)
B. (i)
C. (vi)
D. (iii)
E. (ii)

VI. Answer the questions briefly

Question 1.
What are soft loans?
Answer:
The loans that are sanctioned by the International Development Agency to the Governments for developmental activities are called as soft loans. They are given at very low rate of interest of 50 years.

Question 2.
Did Munich Pact bring peace for some time? How?
Answer:

1. In September 1938, Hitler threatened Czechoslovakia.
2. The British Prime Minister Neville chamberlain initiated talks and signed Munich pact,
3. Hitler promised not to take any more Czech territory.
4. Chamberlain believed that he had achieved “Peace for some time”. But within six months Hitler seized the remainder of Czechoslovakia. So Munich pact has brought peace only for some time.

Question 3.
What do you know about the World Bank?
Answer:
The World bank consists of two main organs namely The International Bank for Reconstruction and Development (IBRD) and the International Development Agency (IDA). Together they are called as the World Bank.

Question 4.
Why did America declare war on Japan?
Answer:

1. The Japanese had attacked the American fleet stationed at Pearl Harbour on December 7, 1941.
2. This disastrous attack forced the Americans to enter into the war.
3. The very next day the USA declared war on Japan.

Question 5.
What are the axis powers and the ally powers of II World War?
Answer:
Germany, Italy, Japan – Axis powers.
Britain, France, Russia, USA – Ally powers.

Question 6.
Name the countries involved in World War II.
Answer:

1. The allies countries were under the leadership of Britain. [Britain, France, Russia and U.S.A]
2. The axis countries were under the leadership of Germany. [Germany, Italy and Japan]

Question 7.
What was the immediate cause of the II World War?
Answer:
The main and immediate cause of the II World War was the aggressive, military, dictatorship attitude of Germany, fast-developing Japan. Hitler’s attack on Poland in 1939, resulted in the declaration of the War by Britain and France.

Question 8.
Write a brief note on security council.
Answer:

1. The council has five permanent members and ten non-permanent members.
2. The five permanent members are the USA, UK, France, Russian Federation and China,
3. The non-permanent members are elected by the General Assembly for two years term,
4. The permanent members have the right to veto for any council decision.
5. Its main responsibility is to maintain International peace and security.

Question 9.
What is ECOSOC? What are its organs?
Answer:
The Economic and Social Council, is the UN organ which is responsible for co-ordinating all the economic and social work of the United Nations. The Regional Economic commissions functioning for regional development across the various regions of the World are its organs. (Asia pacific, West Asia, Europe, Africa, Latin America).

Question 10.
Name some of the specialized agencies of the UNO.
Answer:

1. The World Health Organisation [WHO]
2. The United Nations Educational Scientific and Cultural Organisation(UNESCO)
3. The United Nation’s Children’s Fund (UNICEF)
4. The International Labour Organisation (ILO)
5. Food and Agricultural Organisation (FAO)
6. International Monetary Fund (IMF)
7. International Bank for Reconstruction and Development (IBRD)

VII. Answer the questions given under each caption

Question 1.
Causes of the Second World War.

(a) Name the treaty signed by Japan, Italy and Germany.
Answer:
Italy – Germany – Japan signed the Rome – Berlin – Tokyo Axis treaty.

(b) Mention some of the ideologies that emerged after the First World War.
Answer:
Democracy, Communism, Fascism and Nazism.

(c) What was the policy followed by the statesmen of the major world powers?
Answer:
The statesmen of the major world powers followed the policy of appeasement.

(d) What did Hitler violate?
Answer:
He violated the Munich Pact.

Question 2.
Munich Pact

(a) Who concluded the Munich pact with Germany?
Answer:
In 1938, Prime Minister Chamberlain concluded the Munich pact with Germany.

(b) What did Hitler do in 1939?
Answer:
In 1939, Hitler invaded Czechoslovakia breaking the munich pact that Germany would not attack any other country.

(c) Which act of Hitler made Britain and France declare war on Germany?
Answer:
His act of attack on Poland made Britain and France declare war on Germany.

(d) What were the weapons used in World War II?
Answer:
Heavy military equipment such as tanks, sub-marines, battleships, aircraft carriers, fighter planes and bomber planes.

Question 3.
Organs of the UNO

(a) Name the major organs of the UNO.
Answer:

1. The General Assembly
2. The Security Council
3. The Economic and Social Council
4. The Trusteeship Council
5. The International Court of Justice
6. The Secretariat

(b) Who was elected as the President of the UN General Assembly in 1953?
Answer:
Mrs. Vijaya Lakshmi Pandit

(c) What is the function of the Trusteeship Council?
Answer:
The Trusteeship Council looks after certain territories placed under the trusteeship of the UNO.

(d) How is the Secretary-General of the UNO appointed?
Answer:
The Secretary-General is appointed by the General Assembly on the advice of the Security Council.

Question 4.
Birth of Israel.

(a) What is meant by Holocaust?
Answer:
Holocaust refers to the mass killing of jews by the Germans during World War II.

(b) What was the major outcome of the Holocaust?
Answer:
The major outcome of the Holocaust was the creation of the State of Israel as a homeland for the Jews.

(c) What did the Israel occupy?
Answer:
The Israel has occupied large parts of Palestinian homelands.

(d) From whom does Israel get the support from?
Answer:
Israel get the vast support from the United States.

Question 5.
The United Nations

(a) Who took the first initiative for the formation of the United Nations?
Answer:
The United states and the Britain in 1941.

(b) Name the joint declaration they issued?
Answer:
The Atlantic Charter was the name of the joint declaration they issued.

(c) How many countries accepted the declaration at first?
Answer:
The declaration of the United Nations was accepted by 26 countries, on New years Day 1942.

(d) How many nations signed the charter? When?
Answer:
On June 26, 1945, 51 nations signed the charter.

Question 6.
International Monetary Fund (IMF)

(a) On whose idea the International Monetary Fund was initiated?
Answer:
Harry Dexter white and John Maynard Keynes ideas brought the emergence of IMF.

(b) When was it formally organised?
Answer:
It was formally organised in 1945 with 29 member countries (at present 189).

(c) What were the three main agendas of the IMF?
Answer:

1. To promote International monetary co-operation.
2. To expand International trade.
3. To bring exchange stability.

(d) State the main reason of its funding?
Answer:
The IMF lends money from its resources to countries facing Balance of payment problems.

VIII. Answer in detail

Question 1.
What were the results of Second World War?
Answer:

1. The destruction to life and property was on a much larger scale than the First World War.
2. Over 50 millions lost their lives.
3. It sounded the death knell to dictatorship in Germany and Italy.
4. Germany was occupied by the Allied forces, and later it was divided into two parts.
5. The West Germany was controlled by Britain, France and America and the East Germany by Russia.
6. At the end of the war, Japan was occupied by American forces under General Mc. Arthur.
7. The war weakened Britain and France.
8. America and Russia emerged as super powers.
9. The war did not end totalitarianism in Russia. A cold war started between Russia and America.
10. The war quickened the phase of national movements in Asia and Africa.
11. India, Burma, Egypt, Ceylon and Malaya won their freedom from Britain.
12. Philippines got independence from America.
13. Indo-china got independence from France.
14. Indonesia got independence from the Dutch.
15. The European countries gave up the policy of colonialism and imperialism.
16. The United Nations Organisation was set up to maintain international peace and harmony. It works hard to maintain international co-operation and for the promotion of human welfare.

Question 2.
Write a note on international Monetary Fund (IMF).
Answer:

1. International Monetary Fund was established in 1945 after the Bretton Woods conference in 1944 along with the World Bank.
2. It is located in the Washington in United States.
3. The idea of starting of IMF was given by Harry Dexter, White and John Maynard Keynes, a famous economist.
4. The initial members of the IMF were 29. Now, there are 189 member countries with IMF,
5. The main objectives of IMF include to foster global monetary co-operation, to secure financial stability, to facilitate trade, promote employment, to sustain economic growth and reduce poverty all over the world.
6. The fund lends money to its member countries to correct their balance of payment position if they are unable to pay for their imports.
7. The funding from IMF is not very easy as it strictly imposes restrictions on lending.
8. It imposes the developing nations to tighten the budgets and reduce fiscal expenditure.

Question 3.
Write a note on the UN Commission of Human Rights.
Answer:

1. Human Rights means the fundamental freedom for all human beings without any differences in race, sex, language and religion.
2. The UN efforts to protect human rights on a global basis resulted in the formation of the UN commission on Human Rights.
3. A committee was set up for its formation. It was headed by the wife of FDR of USA, after his death.
4. The other members of the commission included Charles Malik from Lebanon, P.C.Chang from China, Rene Casin from France.
5. The Commission set forth with 30 articles.
6. The UN adopted this historic charter on 10th December 1948.
7. This day, the 10th December is observed as Human Rights Day all over the World.
8. According to the Franklin and Eleanor institute in New York, reports, from 1948 till now, nearly 90 National constitutions are part of this Human Rights Commission of UN.

Students can download 10th Social Science History Chapter 2 The World Between Two World Wars Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions History Chapter 2 The World Between Two World Wars

Samacheer Kalvi 10th Social Science The World Between Two World Wars Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
With whom of the following was the Lateran Treaty signed by Italy?
(a) Germany
(b) Russia
(c) Pope
(d) Spain
Answer:
(c) Pope

Question 2.
With whose conquest did the Mexican civilization collapse?
(a) Heman Cortes
(b) Francisco Pizarro
(c) Toussaint Louverture
(d) Pedro I
Answer:
(a) Heman Cortes

Question 3.
Who made Peru as part of their dominions?
(a) English
(b) Spaniards
(c) Russians
(d) French
Answer:
(b) Spaniards

Question 4.
Which President of the USA pursued “Good Neighbour” policy towards Latin America?
(a) Roosevelt
(b) Truman
(c) Woodrow Wilson
(d) Eisenhower
Answer:
(a) Roosevelt

Question 5.
Which part of the world disliked dollar imperialism?
(a) Europe
(b) Latin America
(c) India
(d) China
Answer:
(b) Latin America

Question 6.
Who was the brain behind the apartheid policy in South Africa?
(a) Verwoerd
(b) Smut
(c) Herzog
(d) Botha
Answer:
(a) Verwoerd

Question 7.
Which quickened the process of liberation in South America?
(a) Support of US
(b) Napoleonic Invasion
(c) Simon Bolivar’s involvement
(d) French Revolution
Answer:
(b) Napoleonic Invasion

Question 8.
Name the President who made amendment to Monroe Doctrine to justify American intervention in the affairs of Latin America.
(a) Theodore Roosevelt
(b) Truman
(c) Eisenhower
(d) Woodrow Wilson
Answer:
(a) Theodore Roosevelt

II. Fill in the blanks

1. The founder of the Social Democratic Party was ……………
2. The Nazi Party’s propaganda was led by ……………
3. The Vietnam Nationalist Party was formed in ……………
4. The Secret State Police in Nazi Germany was known as ……………
5. The Union of South Africa came into being in May ……………
6. The ANC leader Nelson Mandela was put behind the bars for …………… years
7. …………… were a military nation.
8. Boers were also known as ……………

Answers:

1. Ferdinand Lassalle
2. Josef Goebbels
3. 1927
4. The Gestapo
5. 1910
6. 27
7. Aztecs
8. Afrikaners

III. Choose the correct statement

Question 1.
(i) During World War I the primary task of Italy was to keep the Austrians occupied on the Southern Front.
(ii) Germany took to Fascism much later than Italy.
(iii) The first huge market crash in the US occurred on 24 October 1929.
(iv) The ban on African National Congress was lifted in 1966.
(a) (i) and (ii) are correct
(b) (iii) is correct
(c) (iii) and (iv) are correct
(d) (i), (ii) and (iii) are correct
Answer:
(d) (i), (ii) and (iii) are correct

Question 2.
Assertion (A): A new wave of economic nationalism which expressed itself in protectionism affected the world trade.
Reason (R): This was because the USA was not willing to provide economic aid to the debtor countries.
(a) Both A and R are correct.
(b) A is right but R is not the correct explanation.
(c) Both A and R are wrong.
(d) R is right but it has no relevance to A.
Answer:
(a) Both A and R are correct.

Question 3.
Assertion (A): The Berlin Colonial Conference of 1884-85 had resolved that Africa should be divided into spheres of influence of various colonial powers.
Reason (R): The war between the British and Boers in South Africa, however, was in defiance of this resolution.
(a) Both A and R are right.
(b) A is right but R is not the right reason.
(c) Both A and R are wrong.
(d) A is wrong and R has no relevance to A.
Answer:
(a) Both A and R are right.

IV. Match the Following

Answer:
A. (iv)
B. (v)
C. (i)
D. (ii)
E. (iii)

V. Answer briefly

Question 1.
What do you know of the White Terror in Indo-China?
Answer:
In general, the various periods of violent repression led by the counter-revolutionary forces in any country is called as White terror. In Indo-China, when a large number of peasants revolted against the French government, . headed by the communists. It was crushed by the White terror. Many rebels were killed in this incident.

Question 2.
Discuss the importance of Ottawa Economic Summit.
Answer:
Bilateral trade treaties between Britain and the member states of the British Empire were signed at an economic summit in Ottawa in 1932. In this summit the participants (including India) agreed to give preference to imperial (British) over non-imperial goods.

Question 3.
Explain the Monroe Doctrine.
Answer:
The president of the USA, Monroe declared that if any of the Europeans interfere anywhere in America, it would be equal to waging a war against the Americans. This threat frightened the European powers. By 1930, the whole of South America was free from European domination. This was called the Monroe Doctrine.

Question 4.
What was the result of Mussolini’s march on Rome?
Answer:
In October 1923, in the context of a long ministerial crisis, Mussolini organised the fascist March on Rome. Impressed by the show of force, the king invited Mussolini to form a government.

Question 5.
Point out the essence of the Berlin Colonial Conference, 1884-85.
Answer:
The Berlin colonial conference of 1884-85 put forward the idea that Africa should be divided into spheres of influence of various colonial powers.

Question 6.
How did Great Depression impact on Indian agriculture?
Answer:
The Great Depression had a deep impact on Indian agriculture. The value of farm produce, declined by half, while the land rent to be paid by the peasant, remained unchanged. In terms of prices of agricultural commodities, the obligation of the farmers to the state doubled.

Question 7.
Explain the reason for the Smuts-Herzog alliance.
Answer:
When the world economic depression affected South Africa very badly, Smuts believed that coalition Government was necessary to solve the economic problems of the country. Therefore, the South Africa party and the United party made an alliance in 1934. The alliance continued till 1939,

Question 8.
Define “Dollar Imperialism”.
Answer:
‘Dollar Imperialism’ is the term used to describe the policy of the USA in maintaining and dominating over distant lands through economic aid.

VI. Answer the questions given under each caption

Question 1.
Anti-Colonial Struggle in Indo-China

(a) Define the concept of decolonisation.
Answer:
Decolonisation is a process through which colonial powers transferred institutional and legal control over their colonies to indigenous nationalist government.

(b) What were the three States that formed Indo-China?
Answer:
Cambodia, Laos and Vietnam.

(c) How did Communist ideas help in developing the spirit of anti-colonialism.
Answer:
Communist ideas from mainland China helped in developing the spirit of anti-colonalism in Indo-china. Many became convinced that the considerable wealth of Ind-ochina was benefiting only the colonial power. This aroused the feeling of nationalism which resulted in violence. In 1916 there was a major anti-colonial revolt which was crushed brutally. There were also guerrilla activities in Tongking.

(d) Which was the mainstream political party in Indo-China?
Answer:
The mainstream political party in Indo-china was the Vietnam Nationalist Party. It was composed of the wealthy and middle-class sections of the population.

Question 2.
Ho Chi Minh

(a) Where was Ho Chi Minh born?
Answer:
Ho Chi Minh was bom in Tongking in 1890.

(b) How did Ho Chi Minh become a popular Vietnam Nationalist?
Answer:
In the Paris peace conference, he insisted the right for Vietnam independence. His articles on newspapers the Pamphlet, “French colonialism on Trial’’, made him popular as a Vietnam nationalist.

(c) What do you know of Ho Chi Minh’s Revolutionary Youth Movement?
Answer:
In 1923, he went to Moscow and learnt revolutionary techniques. In 1925, he founded the Revolutionary Youth Movement.

(d) How was the League for Independence called in Indo-China?
Answer:
League for Independence was called as Viet Minh in Indo-China.

Question 3.
Political developments in South America

(a) By which year did the whole of South America become free from European domination?
Answer:
By 1830 the whole of South America was free from European domination.

(b) How many republics came into being from Central America?
Answer:
Five republics came into being from the Central America.

(c) In which year was Cuba occupied by the USA?
Answer:
The USA occupied Cuba in the year 1898.

(d) What made oligarchic regimes unpopular in South America?
Answer:
Economic growth, urbanisation and industrial growth in countries like Argentina, Chile, Brazil, and Mexico helped consolidate the hold of middle class and the emergence of militant working class oganisations. At the same time American power and wealth came to dominate Central and South America. These factors made olgarchic regimes unpopular in South America.

VII. Answer in Detail

1. Trace the circumstances that led to the rise of Hitler in Germany.
Answer:

1. Germany’s defeat and humiliation at the end of the first world war causa! great shock to the German people.
2. A group of seven men including Adolf Hitler met in Munich and founded the National Socialist German Worker’s party which was in short called as Nazi party.
3. His attempt to capture Bavaria in 1923.
4. His National Revolution on the outskirts of Munch took him to the prison.
5. There he wrote his autobiography. Mein Kampf (My struggle) which contained his political ideas.
6. In 1932, Presidential election, the communist party won but refused to collaborate with the social democratics.
7. Thereafter, Hitler became chancellor in 1933, when Von Hindenburg as president.
8. The Nazi state of Hitler, known as Third Reich brought an end to the parliamentary democracy.
9. Hitler replaced the Weimar Republic flag by Swastika symbol of Nazi party.
10. He declared all the other political parties except Nazi party as illegal.
11. He expanded his army of brown shirt and Jack booted wearing men.
12. He abolished trade unions, their leaders were arrested. Strikes become illegal, Labour Front was used by the state to control industry, State also controlled press, theatre, cinema, radio and over education.
13. Hitler secret police, The Gestapo was formed and run by Himmler, and second in command was Heydrich, who concentrated on army camps.
14. Hitler’s foreign policy aimed at restoring the armed strength of Germany.
15. All the above circumstances helped the rise of Hitler in Germany.

Question 2.
Attempt a narrative account of how the process of decolonization happened in India during the inter-war period (1919-39).
Answer:
(i) The decolonisation process started in India with the launch of the Swadeshi Movement in 1905. The outbreak of the First world war in 1914 brought about rapid political and economic changes.
(ii) In 1919, the Government of India Act introduced Dyarchy that provided for elected provinical assemblies as well as for Indian ministers to hold certain portfolios under transferred subjects. The Indian National Congress rejected the arrangements under Dyarchy and decided to boycott the legislature.
(iii) The Government of British India provided incentives for the British iron and steel industry by guaranteeing purchasing contracts. But in case of indigenous industries, support was only in the form of providing ‘technical advice and education’ and the establishment of pioneer factories in new industries sponsored by the government.
(iv) The Government of British India also raised revenue tariffs in the Depression years to gain foreign currency earnings. Britain’s need for gold in the crisis years was met from the export of gold from India. By overvaluing Indian currency, the British made imports cheaper. The currency exchange policy pursued by the British government fuelled tensions between the colonial government and its subjects, and intensified the political agitation against British rule.
(v) The Great Depression shattered Indian agriculture. The value of farm produce declined by half, while the land rent to be paid by the peasant remained intact. The great fall in prices prompted Indian nationalists to demand protection for internal economy. The 1930s saw the emergence of the Indian National Congress as a militant mass movement.

Question 3.
Describe the rise and growth of nationalist politics in South Africa.
Answer:

1. The two main political parties in South Africa were:
   • (a) The Unionist party which was mainly British and
   • (b) The south Africa party which had mainly Afrikaners (or) Boers.
2. Botha was the first Prime Minister who belonged to the South African party ruled in co-operation with the British.
3. But, the militant section of the South African party formed the National party under Herzog.
4. In 1912, The African national Congress was formed by Nelson Mandela. But it was banned and he was put into prison for 27 years.
5. In 1920 elections, the National Party won, with 44 seats..
6. Herzog wanted a twin policy of supremacy of Whites over the Blacks and Afrikaners over British.
7. The South African party was led by smuts, secured 41 seats.
8. In this moment, the Unionist party and the South African party merged together. Therefore Smuts gained majority over National party.
9. In 1924 elections, National party won supported by the Labour Movement, (composed of white miners)
10. The Act passed in 1924 prevented blacks from joining trade Unions. Native blacks suffered in Social, Political and Economic spheres.
11. The Great Economic depression brought sufferings to South Africa, therefore, the South African party and the Nationalist party unite in 1934. This smuts-Herzog alliance lasted till 1939.
12. Herzog resigned when the parliament decided infavour of second world war.
13. Smuts continued as prime minister. When Herzog died, many from that party joined the nationalist.
14. Therefore, in 1948, election Reunified National party won over United party.

VIII. Activity

Question 1.
Each student may be asked to write an assignment on how each sector and each section of population in the USA came to be affected by the Stock Market Crash in 1929.
Answer:
Agriculture sector: The prices of the agricultural crops dropped, so low that many farmers became bankrupt and lost their farms. Livestock was the main source of cash. Com was used to feed Cattle and Pigs. But nothing could help them.

Banking Sector: Confidence in the economy was shattered, Wall street and the banks were no longer seen as reliable. Many refused to put money into stocks. The Federal Reserve did not give aid to banks and small banks collapsed.

Industrial sector: As the country’s economy worsened, local industries affected badly. Production went down. Factories closed. Workers remain unemployed. Almost 15 million people were out of work.

Political Sector: The depression affected politics badly people started disliking Herbert Hoover, the president and his type of laissez faire economics. People voted for Franklin Roosevelt. There was dangerous high U.S debt.

Question 2.
A group project work on Vietnam War is desirable. An album or pictures, portraying the air attacks of the US on Vietnam and the brave resistance put up by the Vietnamese may be prepared.
Answer:
Vietnam war: During the 1950’s and 1960’s the United states fought war to stop communism. Vietnam was a French colony since 1880. They fought for independence and won in 1954. The country was split into North Vietnam and South Vietnam. The United states helped south Vietnam with men and materials. The North Vietnam could control South Vietnam.

In 1969, Richard Nixon, became the president of Vietnam. He started bringing more soldiers into force U.S also increased bombing of North Vietnam. Later, in 1973, they agreed to a cease fire. North, South Vietnamese and U.S.A agreed to stop the war. U.S.A returned home. But communism was not stopped in Vietnam.

Timeline:

Samacheer Kalvi 10th Social Science The World Between Two World Wars Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
The …………… change the political conditions in several countries.
(a) Fascism
(b) Nazism
(c) Depression
(d) Oligarchy
Answer:
(c) Depression

Question 2.
The Greatest craze in America was
(a) Trade
(b) Gambling
(c) Share market
Answer:
(c) Share market

Question 3.
HO-Chi-Minh was greatly influenced by the …………… ideas, that he made him to return to Indo China.
(a) Mas-Tse-Tung
(b) Hitler
(c) Bismarck
(d) Tonking
Answer:
(a) Mas-Tse-Tung

Question 4.
The founder of the fascist party was
(a) Adolf Hitler
(b) Benito Mussolini
(c) Stalin
Answer:
(b) Benito Mussolini

Question 5
…………… became the first Caribbean country to throw off slavery and French Colonial control.
(a) Haiti
(b) Mayapan
(c) Portugal
(d) Lisbon
Answer:
(a) Haiti

Question 6
The great relief was provided to the workers by
(a) ILO
(b) Factory Act
(c) Charter of Labour
Answer:
(c) Charter of Labour

Question 7.
The stock market crash took place in New York in the year:
(a) 1940
(b) 1939
(c) 1929
(d) 1909
Answer:
(c) 1929

Question 8
The Allied armies occupied the resources rich
(a) Rhineland
(b) Green land
(c) Sudentenland
Answer:
(a) Rhineland

Question 9.
In 1923, Hitler attempted to capture power in
(a) Munich
(b) Bavaria
(c) Leipzig
(d) Weimar
Answer:
(b) Bavaria

Question 10.
For some time Hitler was a
(a) Painter
(b) Teacher
(c) Tailor
Answer:
(a) Painter

Question 11.
About six million jews in Europe were killed and the Nazis termed it as:
(a) The final solution
(b) Concentraion camps
(c) Security
(d) Foreign policy
Answer:
(a) The final solution

Question 12.
The Allies were strengthened by the entry of
(a) Austria
(b) America
(c) Poland
Answer:
(b) America

II. Fill in the blanks

1. The unjust nature of the treaty of ………….. led to the rise of fascism in Italy and Germany.
2. Hitler developed violent political base against …………..
3. The Nazi state of Hitler was called as …………..
4. The Social Democratic party played a major role in the formation of the ………….. republic.
5. ………….. in his early days, worked as a cook in a London hotel and later lead a war against USA.
6. The two independent Boer states were Transvaal and the …………..
7. The Act of ………….. made it impossible for the blacks to acquire land in most of their country.
8. The voting right to Blacks was abolished in the …………..
9. The decrease in the value of a Country’s currency is called as …………..
10. Countries in the ………….. agreed to convert paper money into fixed amount of gold.
11. The secret police of Hitler was formed and run by …………..
12. Mein Kampf means …………..
13. A Spaniard named ………….. collapsed the Aztec empire.
14. ………….. declared Brazil’s independence from Portugal.
15. The doctrine of ………….. amended by Roosevelt authorised US intervention in Latin America.

Answers:

1. Versailles
2. Jews
3. Third Reich
4. Weimar
5. Ho-Chi-Minh
6. Orange Free States
7. 1913
8. Cape province
9. devaluation
10. gold standard
11. Himmler
12. My struggle
13. Herman cortes
14. Pedro I
15. 1904

III. Choose the correct statement

Question 1.
(i) The depression changed the political conditions in several countries.
(ii) Mussolini was an elementary school master initially and later became a political journalist with socialistic ideas.
(iii) During World War I, Hitler served the Italian army.
(iv) With the fall of Mussolini, the social democratic party was revived.
(a) (i) and (ii) are correct
(b) Only (Hi) is correct
(c) (iii) and (iv) are correct
(d) (ii) and (iv) are correct
Answer:
(a) (i) and (ii) are correct

Question 2.
(i) Decolonisation process was quickened during the Inter-war period in India.
(ii) The Munroe Doctrine prevented Colonisation of Latin American countries by European powers.
(iii) The economic slump originated in USA in 1929 affected all the countries of
(iv) British setup the Union of South Africa, which was racist in nature.
(a) (ii) and (iv) are correct
(b) (i), (ii), (iii), (iv) are correct
(c) (in) and (iv) are correct
(d) (i) and (ii) are correct
Answer:
(b) (i), (ii), (iii), (iv) are correct

Question 3.
(i) in 1930, Civil disobedience Movement evoked tremendous response in rural India.
(ii) The decision of Britain to involve Indians in the Second World War was a welcoming effect from the Congress Ministry.
(iii) The Ottawa Submit of 1931, helped the colonies to give preference to non-imperial goods.
(iv) Decolonisation process started in India with the introduction of Swadeshi movement in 1905.
(a) (i) and (ii) are correct
(b) (i), (ii) and (iii) are correct
(c) (iii) and (iv) are correct
(d) (i) and (iv) are correct
Answer:
(d) (i) and (iv) are correct

Question 4.
(i) The American and French Revolutions provided inspirations to the Latin Americans.
(ii) Latin American nationalists fought not only with Spain and Portugal but also among each other.
(iii) U.S.A protected the South American republics from Europe.
(iv) U.S.A rejected its right to intervene in Cuban internal affairs.
(a) (i) and (ii) are correct
(b) (i), (ii) and (iii) are correct
(c) (iii) and (iv) are correct
(d) (i) aid (iv) are correct
Answer:
(b) (i), (ii) and (iii) are correct

IV. Assertion and Reason

Question 1.
Assertion (A): After World War I, there was worldwide credit contraction and break down of the International system of exchange.
Reason (R): Many countries left the gold standard and followed devaluation of the currency.
(a) Both A and R are correct.
(b) A is correct but R is not the correct explanation.
(c) Both A and R are wrong.
(d) R is correct but it has no relevance to A.
Answer:
(a) Both A and R are correct.

Question 2.
Assertion (A): In 1990, the ban on ANC was lifted and Mandela was freed.
Reason (R): Apartheid is based on the belief that the political equality of white and black in South Africa would mean Black rule.
(a) Both A and R are correct.
(b) A is correct but R is not the correct explanation.
(c) Both A and R are wrong.
(d) R is correct but it has no relevance to A.
Answer:
(b) A is correct but R is not the correct explanation.

Question 3.
Assertion (A): Jews were removed from Government positions, deprived of citizenship and their establishments were attacked.
Reason (R): Hitler had developed violent political biases against Jews.
(a) Both A and R are correct.
(b) A is correct but R is not the correct explanation.
(c) Both A and R are wrong. ”
(d) R is correct but it has no relevance to A.
Answer:
(a) Both A and R are correct.

Question 4.
Assertion (A): Britain transmitted the effects of depression to its colonies. Reason (R): The great depression of 1929 favoured Britain trade and business.
(a) Both A and R are correct.
(b) A is correct but R is not fhe correct explanation.
(c) Both A and R are wrong.
(d) R is correct but it has no relevance to A.
Answer:
(b) A is correct but R is not the correct explanation.

Question 5.
Assertion (A): Aztecs form Mexico conquered Maya country and ruled for nearly 200 years.
Reason (R): Spaniards, especially Hernan Cortes and Pizarro helped Aztecs to conquer Maya country.
(a) Both A and R are correct.
(b) A is correct but R is not the correct explanation.
(c) Both A and R are wrong.
(d) R is correct but it has no relevance to A.
Answer:
(b) A is correct but R is not the correct explanation.

V. Match the Followings

Question 1.
Match the Column I with Column II.

Answer:
A. (iv)
B. (i)
C. (vi)
D. (ii)
E. (iii)

Question 2.
Match the Column I with Column II.

Answer:
A. (iv)
B. (i)
C. (v)
D. (iii)
E. (vi)

VI. Answer briefly

Question 1.
Why did Fascism emerged in Italy and Germany?
Answer:

1. The first world war gravely weakened the European powers. The trade and financial imbalances left by the war created instabilities throughout the world.
2. The conflict between the working and ruling classes that controlled the government became intense. As a result of this Fascism emerged in Italy and Germany.

Question 2.
How did FDR tackle economic depression?
Answer:

1. The policy formulated to tackle the economic depression by FDR was known as New Deal.
2. It includes Relief, Recovery and Reforms.

Question 3.
What do you mean by Gold Standard?
Answer:
It is a monetary system where a country’s currency value is directly linked to gold. Countries in the Gold standard agreed to convert paper money into a fixed amount of gold.

Question 4.
What are the four pillars of fascism?
Answer:

1. Charismatic Leadership
2. Single party rule under a dictator
3. Terror
4. Economic control

Question 5.
Who were called as Boers?
Answer:
The descendants of original Dutch settlers of South Africa, also known as Afrikaners were called Boers. Their language is Afrikaans. The Boers hated those people whom they referred to as Uitlanders (foreigners).

Question 6.
How did Mussolini seize power?
Answer:

1. On October 30, 1922, the fascists organized a march to Rome and showed their strength.
2. The Government surrendered and the emperor Victor Emanuel III invited Mussolini to form the Government.
3. The fascists seized power without bloodshed under the leadership of Mussolini.

Question 7.
What is meant by Good Neighbour policy.
Answer:
It was the policy of USA after 1933, put forward by Franklin Roosevelt, the president of America. According to the policy, USA would not intervene in the internal affairs of any state and would give economic and technical . assistance to Latin America.

Question 8.
How did Mussolini put an end to the conflict between the pope and King?
Answer:

1. In 1929, Mussolini signed the Latern Treaty with the Pope.
2. By this treaty Mussolini recognized the papacy of the Pope in the Vatican city and the Pope recognized the sovereigty of the King in Rome.
3. Thus the 60 years conflict between Papacy and the Italian Government came to an end.

Question 9.
Define Oligarchy.
Answer:
Oligarchy can be defined as a small group of people having control of a country.

VII. Answer the questions given under each caption

Question 1.
Fascist Party
(a) Who was the founder of the Fascist party?
Answer:
Benito Mussolini

(b) Write the slogans of Mussolini.
Answer:
“Believe, Obey, Fight” and “The More Force, The More Honour”.

(c) What were the aims of Fascism?
Answer:

1. Exaltation of the state.
2. Protection of private property.
3. Spirited foreign policy.

(d) What was the motto of Fascism?
Answer:

1. Everything within the state.
2. Nothing against the state.
3. Nothing outside the state.

Question 2.
Mussolini

(a) When did Mussolini joined the Fascist party?
Answer:
When the fascist party was founded in 1919, he immediately joined the . fascist party.

(b) What did Mussolini organise?
Answer:
Mussolini organise the Fascist March on Rome and showed his force and strength in October 1922.

(c) How was he called?
Answer:
He was called as Duce (the leader) by his followers.

(d) What was made the religion of Italy?
Answer:
The Roman Catholic faith was made the religion of Italy.

Question 3.
Hitler’s Aggressive policy

(a) Why did Hitler conquer territories?
Answer:
Hitler conquered territories to accommodate the growing population and to accumulate resources.

(b) How did he violated the Lacarno treaty of 1925?
Answer:
In 1936, he reoccupied Rhine Land by violating the Lacamo treaty of 1925.

(c) What did he demanded from Poland?
Answer:
Hitler demanded the right to construct a military road connecting East Prussia with Germany through Poland and also the surrender of Danzig.

(d) When did he declared war on Poland?
Answer:
Hitler declared war on Poland on 1st September 1939.

Question 4.
Social Democratic Party

(a) When and where was the social Democratic party founded?
Answer:
Social Democratic party was founded on 23rd May 1863 in Leipzig by Ferdinand Lassalle.

(b) Why did Bismarck out lawed this party from 1878 to 1890?
Answer:
The German superior group of people considered the very existence of the party is a threat to the Security and stability of the newly formed Reich. .

(c) What happened to the social democrats when the party was outlawed?
Answer:
The social democrats were arrested and sent to concentration camps.

(d) When was the party revived?
Answer:
With the fall of Hitler, in 1945 the social Democratic party was revived.

Question 5.
Boer War

(a) Who were called as Boers?
Answer:
The descendants of original Dutch settlers of South Africa, were called as Boers.

(b) With whom did the Boers fought with?
Answer:
Boers fought with British and the last started for three years 1899-1902. British won finally.

(c) What were the states annexed by the British?
Answer:
The British annexed the two Boer states, the Transvaal and Orange free state,

(d) What happened to the two states of Boers and two colonies of British?
Answer:
The four states formed into a union of South Africa in May 1910.

VIII. Answer in detail

Question 1.
Narrate the emergence of Mussolini and his triumph.
Answer:

1. After the treaty of Versailes, in 1919, Italian socialists proclaimed that they follow communism in Russia (Bolsheviks)
2. As a powerful speaker, he supported the use of violence and broke with socialists when they opposed Italy’s entry into the war.
3. In 1919, when Fascist party was founded, he joined it.
4. Fascist raised in strength with support of ex-soldiers, Industrialists and youth.
5. In 1922, he led a march to Rome and showed the king, his force and strength.
6. Impressed by that, the king invited Mussolini to form the government.
7. He advocated dictatorship, and radical authority called as Fascism.
8. In 1924 elections, Fascist secured 65% of votes.
9. When the fairness of the elections were questioned by Matteotti, a socialist leader, he was murdered and opposition party was banned.
10. Assuming the title of Duce in 1926, he became the dictator.
11. In 1929, he signed the Lateran treaty with pope and won over the Roman Catholic church by transferring the Vatican city as an Independent state.
12. He passed law forbidding strikes and locks outs.
13. In 1938, parliament was abolished and was replaced by a body representing the fascist party.

Question 2.
How did Hitler establish Nazi rule in Germany?
Answer:
Adolf Hitler:
He was born in 1889 in Austria. His father was a customs officer. He lost his parents from his earlyhood. So he went to Vienna for job and was a painter for sometime. During the First World War, he joined the army and fought bravely for which he was awarded the Iron cross.

Rise of Nazis party:
After the war, Hitler did not get any job. So he organized a group of men called the National socialists in 1919, which became the Nazist party.

Beer Hall Revolution:

1. In 1923, he made attempt to capture power. It was known as “Beer Hall Revolution”. But he failed in his attempt.
2. He was arrested for high treason and sentenced to five years imprisonment.
3. While he was in prison he wrote a book called “Mein Kampf” (My struggle), which became the Bible of the Nazis.

Capture of power:
Under the inspiring leadership of Hitler, the Nazi party grew in power and number.

1. In the election of 1932, the Nazi party became the 2nd largest group in the German parliament.
2. In 1933, the Nazists became the largest party in the German parliament and Hitler became the Chancellor and Hindenburg as president.
3. On the death of President Hindenburg, he made himself as President and Chancellor.
4. He abolished the Weimar Republic and himself became a dictator.

Question 3.
How did the Munroe Doctrine protected the South American Republics?
Answer:

1. When European kings wanted to help the king of Spain to crush the revolutionaries in the South America Colonies, America Interfered.
2. The President of the USA, Munroe declared that if Europeans interfered anywhere in America, North or South, it is equal to wage a war against the United states.
3. The threat of the president of USA frightened the European powers.
4. By this, in 1830, the whole of South America was free from European domination.
5. In 1898, after defeating the Spanish, USA occupied Cuba and Puerto Rico.
6. USA retained its right to intervene in Cuban internal affairs.
7. Later Roosevelt made an important amendment to the Munroe doctrine in 1904. It authorized U.S, Intervention in Latin America.
8. Thus, the Munroe Doctrine protected the American continent from European affairs.

Students can download 10th Social Science History Chapter 1 Outbreak of World War I and Its Aftermath Questions and Answers, Notes, Samacheer Kalvi 10th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Social Science Solutions History Chapter 1 Outbreak of World War I and Its Aftermath

Samacheer Kalvi 10th Social Science Outbreak of World War I and Its Aftermath Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
What were the three major empires shattered by the end of First World War?
(a) Germany, Austria Hungary, and the Ottomans
(b) Germany, Austria-Hungary, and Russia
(c) Spain, Portugal and Italy
(d) Germany, Austria-Hungary, Italy
Answer:
(a) Germany, Austria Hungary, and the Ottomans

Question 2.
Where did the Ethiopian army defeat the Italian army?
(a) Delville
(b) Orange State
(c) Adowa
(d) Algiers
Answer:
(c) Adowa

Question 3.
Which country emerged as the strongest in East Asia towards the close of nineteenth century?
(a) China
(b) Japan
(c) Korea
(d) Mongolia
Answer:
(b) Japan

Question 4.
Who said “imperialism is the highest stage of capitalism”?
(a) Lenin
(b) Marx
(c) Sun Yat-sen
(d) Mao Tsetung
Answer:
(a) Lenin

Question 5.
What is the Battle of Marne remembered for?
(a) air warfare
(b) trench warfare
(c) submarine warfare
(d) ship warfare
Answer:
(b) trench warfare

Question 6.
Which country after the World War I took to a policy of isolation?
(a) Britain
(b) France
(c) Germany
(d) USA
Answer:
(a) Britain

Question 7.
To which country did the first Secretary General of League of Nations belongs?
(a) Britain
(b) France
(c) Dutch
(d) USA
Answer:
(a) Britain

Question 8.
Which country was expelled from the League of Nations for attacking Finland?
(a) Germany
(b) Russia
(c) Italy
(d) France
Answer:
(b) Russia

II. Fill in the blanks

1. Japan forced a war on China in the year ……………….
2. The new state of Albania was created according to the Treaty of ………………. signed in May 1913.
3. Japan entered into an alliance with England in the year ……………….
4. In the Balkans ………………. had mixed population.
5. In the battle of Tannenberg ………………. suffered heavy losses.
6. ………………. as Prime Minister represented France in Paris Peace Conference.
7. ………………. became Prime Minister leading a new coalition of liberals and moderate Socialists before Lenin established the Bolshevik government.
8. Locarno Treaty was signed in the year ………………..

Answers:

1. 1894
2. London
3. 1902
4. Macedonia
5. Russia
6. Clemenceau
7. Kerensky
8. 1925

III. Choose the correct statement

Question 1.
(i) Italy remained a neutral country when the World War broke out.
(ii) Italy was much disappointed over the peace settlement at Versailles.
(iii) The Treaty of Sevres was signed with Italy.
(iv) Italy was denied even small places such as Trieste, Istria and the south Tyrol.
(a) (i) and (ii) are correct
(b) (iii) is correct
(c) (iv) is correct
(d) (i), (iii) and (iv) are correct
Answer:
(a) (i) and (ii) are correct

Question 2.
(i) The Turkish Empire contained many non-Turkish people in the Balkans.
(ii) Turkey fought on the side of the central powers
(iii) Britain attacked Turkey and captured Constantinople
(iv) Turkey’s attempt to attack Suez Canal but were repulsed.
(a) (i) and (ii) are correct
(b) (i) and (Hi) are correct
(c) (iv) is correct
(d) (i), (ii) and (iv) are correct
Answer:
(d) (i), (ii) and (iv) are correct

Question 3.
Assertion (A): Germany and the United States were producing cheaper manufactured goods and capturing England’s markets.
Reason (R): Both the countries produced required raw material for their industries.
(a) Both A and R are correct
(b) A is right but R is not the correct reason
(c) Both A and R are wrong
(d) R is right but it has no relevance to A.
Answer:
(b) A is right but R is not the correct reason

Question 4.
Assertion (A): The first European attempts to carve out colonies in Africa resulted in bloody battles.
Reason (R): There was stiff resistance from the native population.
(a) Both A and R are correct
(b) A is right but R is not the correct reason
(c) Both A and R are wrong
(d) R is right but it has no relevance to A.
Answer:
(a) Both A and R are correct

IV. Match the following

Answers:
A. (iii)
B. (iv)
C. (ii)
D. (v)
E. (i)

V. Answer briefly

Question 1.
How do you assess the importance of Sino-Japanese War?
Answer:
Sino-Japanese war took place in the years 1894 – 1895. China was defeated in the war. Japan annexed the Liaotung peninsula with Port Arthur inspite of warning given by three great powers, Russia, Germany and France. By this Japan had proved that it was the strongest nation of the East – Asia.

Question 2.
Name the countries in the Triple Entente.
Answer:
Britain, France and Russia.

Question 3.
What were the three militant forms of nationalism in Europe?
Answer:
The three militant forms of nationalism were, England’s Jingoism, France’s Chauvinism and Germany’s Kultur.

Question 4.
What do you know of trench warfare?
Answer:
Trench warfare is a type of land warfare using occupied fighting lines consisting largely of military trenches, in which troops are well-protected from the enemy’s small arms fire and are substantially sheltered from artillery. It is a warfare in which opposing armed forces attack, counterattack, and defend from relatively permanent systems of trenches dug in the ground.

Question 5.
What was the role of Mustafa Kemal Pasha?
Answer:
When Britian attacked Turkey directly and tried to capture Constantinople, Turks put up a brave fight and Mustafa Kemal Pasha played a great role to win freedom for the country. He put an end to the sultanate and caliphate. He modernized it and changed it out for recognition.

Question 6.
Highlight the global influence of Russian Revolution?
Answer:
The Russian Revolution fired people’s imagination across the world. In many countries, communist parties were formed. The Russian communist government encouraged the colonies to fight for their freedom and gave all support to them. Debates over key issues, land reforms, social welfare, workers’ rights, and gender equality taking place in a global context.

Question 7.
List out any two causes for the failure of the League of Nations.
Answer:
League did not had the military power of its own , it could not enforce its decisions. Even though, it had world wide membership it become very much the center of European diplomacy.

VI. Answer all the questions given under each caption

Question 1.
Imperialism
(a) What do you know of monopoly capitalism?
(b) How did Japan emerge as an imperial power?
(c) Why did the industrial countries need colonies in the nineteenth century?
(d) What were the contrasts capitalism produced?
Answer:
(a) Capitalism based on the principle of free -trade without any control or regulation by the state is called monopoly Capitalism.
(b) Japan emerged as an imperial power by annexing the Liaotung peninsula with Port Arthur inspite of warning given by Russia, Germany and France.
(c) Because colonies acted as a market for surplus goods and vast supplies of raw materials.
(d) Capitalism produced extreme poverty and extreme wealth. Slum and skyscraper. Empire state and dependent exploited colony.

Question 2.
German Emperor

(a) What was the nature of Emperor Kaiser Wilhelm II of Germany?
Answer:
Emperor Kaiser Wilhelm II of Germany was ruthlessly assertive and aggressive. He proclaimed that Germany would be the leader of the world.

(b) What was the violent form of Germany called?
Answer:
It was called Germany’s Kultur.

(c) Why did Kaiser Wilhelm intervene in the Morocco affair?
Answer:
The British agreement with France over the latter’s interest in Morocco was consented by Germany. So Kaiser Wilhelm II of Germany intentionally recognised the independence of the Sultan and demanded an international conference to decide on the future of Morocco.

(d) What happened to Germany’s colonies in Africa?
Answer:
The German colonies in western and eastern Africa were attacked by the Allies. As these colonies were quite far off from Germany they could not receive any immediate help, and therefore had to surrender to the Allies.

Question 3.
Balkan Wars
(a) Why was Balkan League formed?
(b) What was the outcome of the first Balkan War?
(c) Who were defeated in this war?
(d) What was the name of the Treaty signed at the end of this second Balkan War?
Answer:
(a) To control Greece, Serbia, Bulgaria and Montenegro in succeeding Balkans from Turks, in March 1912 the Balkan League was formed.
(b) The Balkan League defeated the Turkish forces in the 1st Balkan war.
(c) Turkey and Bulgaria were defeated in this war.
(d) Treaty of Bucharest in August 1913.

VII. Answer the following in detail

Question 1.
Discuss the main causes of the First World War.
Answer:
The causes of the First World War are given below:

1. Formation of European alliances and counter alliances
2. Emergence of violent forms of nationalism in countries like England, France and Germany
3. Aggressive attitude of the German Emperor Kaiser Wilhelm II
4. Hostility of France towards Germany
5. Opportunity for imperial power politics in the Balkans
6. The Balkans wars
7. Immediate cause which included the assassination of Archduke Franz Ferdinand, nephew and heir to Franz Joseph, Emperor of Austria-Hungary, by Princip, a Bosnian Serb, on 28 June 1914.

Question 2.
Highlight the provisions of the Treaty of Versailles relating to Germany.
Answer:

1. All the central powers were directed to pay war indemnity especially Germany was to pay heavy amount for the losses suffered.
2. Germany had to pay 6,600 million pounds as per the Reparation Commission, but can be paid in installments.
3. The Germans should not have submarines and airforce, but can have a small navy and an army of one lakh men.
4. Austria and Germany separated and Austria was given independence.
5. All German colonies came under the mandated territories of League of nations.
6. Germany had to give up all her overseas possessions, rights and titles to the allies.
7. Germany surrendered Alsace-Lorraine to France.
8. She signed the Treaty of Brest-Litovsk with Russia and the treaty of Bucharest with Bulgaria.
9. Rhineland was to be occupied by the allies. East of Rhineland area was to be demilitarised.
10. Poland was recreated with a corridor to Baltic containing the port of Danzig of Germany.

Question 3.
Explain the course of the Russian Revolution under the leadership of Lenin.
Answer:

1. Lenin was in Switzerland when the revolution broke out in Russia. He wanted to continued revolution.
2. His slogan of “All power to the Soviets” soon won over the workers’ leaders. Devastated by war time shortages, the people were attracted by the slogan of ‘Bread, Peace and Land’.
3. In October Lenin persuaded the Bolshevik Central Committee to decide on immediate revolution. Trotsky prepared a detailed plan
4. On 7 November the key government buildings, including the Winter Palace, the Prime Minister’s headquarters, were seized by armed factory workers and revolutionary troops
5. On 8 November 1917a new Communist government was in office in Russia. Its head this time was Lenin. The Bolshevik Party was renamed the Russian Communist Party.

Question 4.
Estimate the work done by the League of Nations, pointing out the reasons for its failure?
Answer:

1. League of nations was formed in 1920 with the twin objective of avoiding war and to maintain peace in the world.
2. The main work done by the League was to solve the dispute arose between Sweden and Finland over the sovereignity of Aaland Island. It ruled that the island should go to Finland.
3. League solved the frontier dispute between Poland and Germany in upper Silesia.
4. When dispute arose between Greece and Bulgaria in 1925, Greece invaded Bulgaria and the League ordered a ceasefire.
5. League had been successful in signing the Locarno Treaty in 1925 by which Germany,France, Belgium, Great Britain and Italy mutually guaranteed peace in Western Europe.
6. The main reason for the failure of the League was Italy, Japan and Germany headed by dictators refused to be bound by the orders of the League and started violation and League rules.
7. When League condemned the violation, they withdrew their membership.
8. League did not had a military power of its own.
9. Though it had a world-wide membership, it became the center of European diplomacy.
10. The League remained a passive witness to events, issues and incidents of violations therefore finally dissolved in 1946.

VIII. Activity

Question 1.
Students can be taught to mark the places of battles and the capital cities of the countries that were engaged in the War.
Answer:
(a) Battles of I World war:
(i) Battle of Tannenberg
(ii) Battle of Marne
(iii) Battle of Gallipoli
(iv) Battle of Jutland
(v) Battle of Verdun
(vi) Battle of Passchendaele
(vii) Battle of Caporetto
(viii) Battle of Cambrai
(ix) Battle of the Somme.

(b) Capital cities of countries engaged in the IWW.
Central powers & Capital:
(i) Germany – Berlin
(ii) Austria – Vienna
(iii) Hungary – Budapest
(iv) Italy – Rome
(v) Ottoman Empire – Istanbul, Bursa, Edirne, Sogut
(vi) Bulgaria – Sofia
(vii) Tu rkey – An ka ra
Allies- Capital:
(i) Great Britain – London
(ii) France – Paris
(iii) Russia – Moscow
(iv) Italy – Rome
(v) United States – Washington D. C

Question 2.
An assignment or a project work on the role of Indian soldiers in different battle fields across the globe and the casualties they suffered during the War be attempted by the students.
Answer:
During the War, the Indian Army contributed a large number of divisions and independent brigades to the European, Mediterranean and the Middle East. The Indian Army fought against the German Empire in German East Africa and on the Western Front. Indian divisions were also sent to Egypt, Gallipoli and nearly 700,000 served in Mesopotamia against the Ottoman Empire. While some divisions were sent overseas others had to remain in India guarding the North West Frontier and on internal security and training duties.

In addition to the permanent divisions, the Indian Army also formed a number of independent brigades. As part of the Southern Army the Aden Brigade was stationed in the Aden Protectorate on the strategically important naval route from Europe to India, where there was limited fighting.

The Bannu Brigade, the Derajat Brigade and the Kohat Brigade were all part of the Northern Army and they were deployed along the North West Frontier. The South Persia Brigade was formed in 1915 at the start of the Persian Campaign to protect the Anglo- Persian oil installations in south Persia and the Persian Gulf.

On the outbreak of war, the Indian Army had 150,000 trained men and the Indian Government offered the services of two cavalry and two infantry divisions for service overseas. The force known as Indian Expeditionary Force A was attached to the British Expeditionary Force and the four divisions were formed into two army corps: an infantry Indian Corps and the Indian Cavalry Corps.

Indian Expeditionary Force B consisted of the 27th (Bangalore) Brigade from the 9th (Secunderabad) Division and an Imperial Service Infantry Brigade, a pioneer battalion, a mountain artillery battery and engineers were sent to Tanganyika with the task of invading German East Africa. Force C was formed from the Indian Army’s 29th Punjabis, together with half battalions from the Princely states of Jind, Bharatpur, Kapurthala and Rampur. The largest Indian Army force to serve abroad was the Indian Expeditionary Force D in Mesopotamia, under the command of Lieutenant-General Sir John Nixon.

Over one million Indian troops served overseas, of whom 62,000 died and another 67,000 were wounded. In total at least 74,187 Indian soldiers died during the War. Field-Marshal Sir Claude Auchinleck, Commander-in-Chief of the Indian Army from 1942, commented that the British “couldn’t have come through both wars [World War I and II] if they hadn’t had the Indian Army.”

IX. Map Work

Mark the following countries on the world map.

1. Great Britain
2. Germany
3. France
4. Italy
5. Morocco
6. Turkey
7. Serbia
8. Bosnia
9. Greece
10. Austria-Hungary
11. Bulgaria
12. Rumania

Timeline:

Samacheer Kalvi 10th Social Science Outbreak of World War I and Its Aftermath Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
The Treaty of serves was signed with:
(a) Austria
(b) Hungary
(c) Turkey
(d) Bulgaria
Answer:
(c) Turkey

Question 2.
The policy of imperialism followed by the European countries from 1870-1945 was known as ……
(a) New imperialism
(b) Military imperialism
(c) Neo-imperialism
Answer:
(a) New imperialism

Question 3.
President Woodrow Wilson put forward ………….. points in the League of nations.
(a) 12
(b) 11
(c) 10
(d) 14
Answer:
(d) 14

Question 4.
With a modem army and navy, ….. had emerged as an advanced industrialised
power.
(a) Germany
(b) Japan
(c) Italy
Answer:
(b) Japan

Question 5.
Germany surrendered in:
(a) 1917
(b) 1918
(c) 1919
(d) 1916
Answer:
(b) 1918

Question 6.
The ‘Sphere of influence’ was adopted by the European countries in ……
(a) Japan
(b) China
(c) India
Answer:
(b) China

Question 7
………….. is the name of the parliament of Russia.
(a) Tsar
(b) Trotsky
(c) Duma
(d) Rasputin.
Answer:
(c) Duma

Question 8.
The word “Imperialism” is derived from ……
(a) Greek
(b) German
(c) Latin
Answer:
(c) Latin

Question 9.
Nicholas II abdicated from his throne on ……………. 1917.
(a) March 12
(b) March 15
(c) November 18
(d) October 14
Answer:
(b) March 15

Question 10.
The development of ……. speeded the movements of goods between colonies and other countries.
(a) Roadways
(b) Waterways
(c) Railways
Answer:
(c) Railways

II. Fill in the blanks

1. The biggest outcome of the first world war was the …………….
2. The Trust is an industrial organisation in the …………….
3. The Imperialist Prime Minister of South Africa was called …………….
4. Cartel means ……………. of enterprises in the same field of business.
5. The treaty of ……………. was signed after the Russo-Japanese war and Japan got back port Arthur.
6. The violent form of nationalism in Germany was called as …………….
7. France and Germany were old …………….
8. The enemity between and led to the outbreak of war in 1914.
9. The new state of Albania was created according to the treaty of ……………. signed in 1913.
10. Russia suffered heavy loses in the battle of …………….
11. Trench warfare was the style followed in the battle of …………….
12. Russia signed the treaty of ……………. with Germany.
13. Italy formally joined the allies in …………….
14. Battle of Jutland is a ……………. battle.
15. ……………. is the name of the American ship sunk by Germany.
16. ……………. was one of the principle in the fourteen points of Paris peace conference.
17. The war conditions led to the ……………. movement in India.
18. ……………. modernised Turkey and changed it out of all recognition.
19. £ is the symbol of …………….
20. The Bolshevik party was renamed as ……………. party.

Answers:

1. Russian Revolution
2. USA
3. Cecil Rhodes
4. Association
5. Portsmouth
6. Kultur
7. Rivals
8. Austria and Serbia
9. London
10. Tannenburg
11. Marne
12. Brest Litovsk
13. 1916
14. Naval
15. Lusitania
16. Self determination
17. Home Rule
18. Pound sterling
19. Kemal Pasha
20. Russian communist

III. Choose the correct statements.

Question 1.
(i) The Industrial achievements of Germany in the later half of the 19th Century gave her a dominating position in Europe.
(ii) When Germany came to the scene of exploitation, it became weak in its military power.
(iii) When there was nowhere else to expand, imperialist countries grab other’s possession.
(iv) Russia, Britain and France joined in the scramble for colonies.
(a) (i) and (ii) are correct
(b) (i) and (iii) are wrong
(c) (ii) and (iv) are wrong
(d) (i), (ii) and (iv) are correct
Answer:
(c) (ii) and (iv) are wrong

Question 2.
(i) The Central powers consisted of Germany, Austria-Hungary, Turkey and Bulgaria.
(ii) Italy strongly supported Germany.
(iii) In April 1916, Britain, France and Italy signed the Treaty of London.
(iv) Italy agreed to enter the war against the central powers in-return of this territory after the war.
(a) (i), (ii) and (iii) are correct
(b) (ii), (iii) and (iv) are correct
(c) (i) and (iii) are correct
(d) (i) and (iv) are correct
Answer:
(d) (i) and (iv) are correct

Question 3.
(i) Trenches are ditches dug by troops enabled soldiers.
(ii) It was done to protect themselves from enemy fire.
(iii) The battle of Jutland is a memorable one for Trench war fare.
(iv) Trench system used in the first world war consisted of six to seven trench lines running parallel to each other.
(a) (ii) and (iv) are correct
(b) (i) and (ii) are correct
(c) (i) and (iv) are correct
(d) (iii) and (iv) are correct
Answer:
(b) (i) and (ii) are correct

Question 4.
(i) The main provision of the Versailles treaty was that all central powers were directed to pay war indemnity.
(ii) All the German colonies became mandated territories under the League of nations.
(iii) The Saar coal mine was given to Bulgaria.
(iv) Northern Schleswig was given to France.
(a) (iii) and (iv) are correct
(b) (i) and (ii) are correct
(c) (i), (ii), (iv) are correct
(d) (ii) and (iv) are correct
Answer:
(b) (i) and (ii) are correct

Question 5.
(i) Triple Alliance was signed in 1882 between Germany, Austria-Hungary and Italy.
(ii) Entente cordiale was signed in 1906 between Britain and Russia.
(iii) Triple Entente was signed between Britain, France and Russia.
(iv) The Britain violation of Belgian neutrality forced German to enter the war.
(a) (i), (ii), (iv) are correct
(b) (iii) and (iv) are correct
(c) (i) and (iii) are correct
(d) (ii) and (iv) are correct
Answer:
(c) (i) and (iii) are correct

IV. Assertion and Reason

Question 1.
Assertion (A): Inspite of warning of the three great powers, Russia, Germany and France, Japan annexed the Liaotung Peninsula with Port Arthur.
Reason (R): Japan proved that it was the strongest nation of the East Asia.
(a) Both A and R are correct
(b) A is right but R is not the correct reason
(c) Both A and R are wrong
(d) R is right but it has no relevant to A
Answer:
(a) Both A and R are correct

Question 2.
Assertion (A): Two peace conferences were held at the Hague in Holland in 1899 and in 1907.
Reason (R): Lenin of Russia wanted to bring Universal peace and suggested these conferences.
(a) Both A and R are correct
(b) A is right but R is not the correct reason
(c) Both A and R are wrong
(d) R is right but it has no relevant to A
Answer:
(b) A is right but R is not the correct reason

Question 3.
Assertion (A): Italy formally joined with the allies fighting with Austria, initially sustained, but finally collapsed.
Reason (R): Germans came to Austria’s help.
(a) Both A and R are correct
(b) A is right but R is not the correct reason
(c) Both A and R are wrong
(d) R is right but it has no relevant to A
Answer:
(a) Both A and R are correct

Question 4.
Assertion (A): In Germany and Austria, women and children suffered from hunger and privation.
Reason (R): Aeroplanes were used for bombing targeted Civilian population.
(a) Both A and R are correct
(b) A is right but R is not the correct reason
(c) Both A and R are wrong
(d) R is right but it has no relevant to A
Answer:
(b) A is right but R is not the correct reason

Question 5.
Assertion (A): Marxists in Russia had the fortune of getting Lenin as their leader.
Reason (R): Tsar Nicholas li was under the strong influence of his wife Alexandra.
(a) Both A and R are correct
(b) A is right but R is not the correct reason
(c) Both A and R are wrong
(d) R is right but it has no relevant to A
Answer:
(b) A is right but R is not the correct reason

Question 6.
Assertion (A): The League of nations could apply the principle of collective security.
Reason (R): It was supported by Italy, Japan and Germany.
(a) Both A and R are correct
(b) A is right but R is not the correct reason
(c) Both A and R are wrong
(d) R is right but it has no relevant to A
Answer:
(c) Both A and R are wrong

V. Match the following

Question 1.
Match the Column I with Column II.

Answer:
A. (iv)
B. (v)
C. (i)
D. (ii)
E. (iii)

Question 2.
Match the column I with column II.

Answer:
A. (iv)
B. (i)
C. (v)
D. (ii)
E. (iii)

VI. Answer the following questions briefly

Question 1.
What was the aim of the capitalist countries?
Answer:
The aim of the capitalistic countries was to produce more and more. The surplus wealth that was produced was used to build more factories, railways, steamship and other such undertakings.

Question 2.
What is colonialism?
Answer:
(i) Colonialism refers to the policy of acquiring and maintaining colonies especially for exploitation.
(ii) It also means that it is a relationship between an indigenous majority and a minority foreign invaders.

Question 3.
What was the immediate cause of the first world war?
Answer:
The nephew and heir to Franz Joseph, Emperor of Austria-Hungary. The Arch duke Franz Ferdinand was killed by Princip a Serbian of Bosnia. This was the immediate cause as Austria got help from Germany and Serbia got help from Russia. Thus the war began in 1914.

Question 4.
How did China became an International colony?
Answer:

1. The Boers were defeated by foreign powers.
2. When they reached Peking, the capital of China, Empress Dowager fled from the capital,
3. The U.S.A. and England formulated the Open Door Policy or Me Too Policy.
4. The Chinese territories were partitioned among the foreign powers for trade rights. Thus China became an international colony.

Question 5.
What do you understand by Paris peace conference?
Answer:
The Paris peace conference held in January 1919 two months after the signing of the armistice.
Woodrow Wilson of America and Lloyd George of Britain were the important personalities. On 28 June 1919, the peace treaty was signed in The Hall of Mirrors at Versailles.

Question 6.
What was the immediate cause of the First World War?
Answer:

1. In 1908, Austria annexed Bosnia and Herzegovina against the Congress of Berlin.
2. Austrian Prince Francis Ferdinand and his wife were assassinated at Sarajevo on June 28, 1914.
3. Austria sent an ultimatum to Serbia, but Serbia ignored it.
4. So Austria declared war on Serbia on 28th July 1914.

Question 7.
Write the slogans raised by Lenin that attracted soviet people.
Answer:
“All power to the soviets” and “Bread, Peace and Land” were the slogans raised by Lenin that attracted the soviet people who were devastated by war time shortages.

Question 8.
Write any two terms of the Treaty of Versailles.
Answer:

1. A huge war indemnity was imposed on Germany. Her army was reduced.
2. The overseas possessions of Germany were divided among the victorious nations.

Question 9.
Write any two objectives of the League.
Answer:
The two main objective of the League of Nations was (i) To avoid war and to maintain peace in the world, (ii) To promote international co-operation in economic and social affairs.

Question 10.
What do you mean by Russian Revolution?
Answer:
The fall of monarch in February 1917 and the events of October are known as the Russian Revolution.

Question 11.
What is Duma? Why did the Tsar dismiss the first Duma within 75 days of its election?
Answer:
An elective legislative assembly established in 1905 by Nicholas II in Russia is known as Duma. Because the Tsar did not want anyone to question his authority, so he dismissed the first Duma within 75 days.

VII. Answer all the questions given under each caption

1. Characteristics of Imperialism

(a) What led to concept of Imperialism?
Answer:
Capitalism inevitably led to the concept of Imperialism.

(b) What was Lenin idea on Imperialism?
Answer:
According to Lenin, imperialism is the highest stage of Capitalism.

(c) What were the purposes for which the colonies were made use of?
Answer:
The colonies served as a market for goods and also vast suppliers of raw materials like cotton, Rubber etc.

(d) What was the logic behind Imperialism apart from colonisation?
Answer:
The logic behind Imperialism apart from colonisation was, total militarisation and total war.

2. The ambition of Germany

(а) Who was the ruler of Germany during the First World War?
Answer:
Kaiser Wilhelm II.

(b) What did he believe?
Answer:
He believed that Germany alone was competent to rule the whole world.

(c) What could not be tolerated by him?
Answer:
He could not tolerate the British saying that the Sun never sets in the British Empire.

3. Naval Battles

(a) Name the Naval battle that took place in 1916?
Answer:
In 1916, the Naval battle had taken place in the North sea called as Battle of Jutland.

(b) Which country started the Sub-marine warfare thereafter?
Answer:
Germany started their Submarine warfare thereafter.

(c) Name the ship that bombarded Madras?
Answer:
The ship that bombarded Madras was the famous Emden ship.

(d) Name the American ship torpedoed by a German Submarine.
Answer:
Lusitania, an American ship was torpedoed by a German Submarine.

4. Course of the First World War

(a) Give the duration of the First World War.
Answer:
From July 28, 1914 to November 11, 1918.

(b) Who were called the Central Powers?
Answer:
The countries which were on the side of Germany were called the Central Powers.

(c) Who were called the Allies?
Answer:
The countries which were on the side of Britain were called as the Allies.

(d) What and all were used in war?
Answer:
Artillery, Tanks and submarines were used in the war.

5. Lenin

(a) Where was he born?
Answer:
Lenin was bom in 1870 near the middle Volga to educated parents.

(b) What was his belief?
Answer:
Lenin believed that the wav for freedom was through mass action.

(c) When and why was he arrested?
Answer:
He was arrested in 1895 and kept in Serbia for encouraging the ideas of Marxism to the factory workers in St. Petersburg.

(d) How did he form the Bolshevik party?
Answer:
Lenin gained the support of small majority called Bolshmstvo known as Bolsheviks which later became the Bolshevik party.

6. Results of the war

(a) How were the terms of the treaties drafted?
Answer:
Based upon the fourteen points of the American President Woodrow Wilson.

(b) What did Germany surrendered to France?
Answer:
Germany surrendered Alsace and Lorraine to Europe.

(c) Where was monarchy abolished?
Answer:
In Germany, Russia, Austria and Turkey.

(d) Name the new Republics.
Answer:
Czechoslovakia and Poland.

VIII. Answer the following in detail

Question 1.
Write a note on the structure and composition of its League of Nations.
Answer:

1. The covenant of the League of Nations was formed at the Paris peace conference after the first world war.
2. President of USA -Woodrow Wilson largely supported for this task to be accomplished.
3. The structure of the League consist of the Assembly, the council, the Secretariat, the permanent court of Justice and the International Labour organization.
4. Each member country was represented in the Assembly.
5. Each member country’ and had one vote and also possessed the right of veto.
6. Britain, France, Italy, Japan and United States were originally declared permanent members of the council.
7. The council was the executive of the League.
8. The staff of the secretariat was appointed by the Secretary General in consultation with the council.
9. The court of Justice consisted of fifteen Judges.
10. The International Labour organization comprised a Secretariat. The general conference will include four representatives from each country.
11. The first secretary general of League of Nations was Sir Eric Drummond from Britain.

Question 2.
What were the results of the first world war?
Answer:
The Paris Peace Conference:

1. The first world war came to an end by the Paris Peace Conference of 1919.
2. The city of Danzig was internationlized.
3. Lithuvania, Latvia and Estonia were granted independence.

The formation of the League of Nations:

1. The first world war brought untold miseries to people.
2. All the nations wanted a permanent body to maintain peace in the world. So the League of Nations was formed in 1920.
3. The victorious nations forced the defeated nations with unfair treaties. It sowed the seed for the second world war.

Question 3.
What was the impact of First world war on India?
Answer:

1. The first world war had multiple effects on the Indian economy, society and politics.
2. Indians had taken an active part in the war on the side of Britain, believing that they would reward Independence after the war.
3. But also, disappointment was rewarded to the Indians.
4. Indian soldiers asked to serve in Europe, Africa and West Asia.
5. India contributed £230 million in cash and over £125 million in loan towards war expenses.
6. India also sent war materials to the value of £ 250 million .
7. There were economic distress all over the country.
8. Towards the end of the war, India suffered under the world wide epidemic of influenza.
9. Home Rule Movement arose in India due to the war conditions.
10. The congress split of extremists and moderates reunited.
11. The Ottoman Empire under the Turkish Sultan was defeated in World war I and the territories shared between Britain and France.
12. This led to the formation of Khilafat Movement in India.

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Maths Guide Pdf Chapter 2 Complex Numbers Ex 2.3 Textbook Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Maths Solutions Chapter 2 Complex Numbers Ex 2.3

Question 1.
If z₁ = 1 – 3i, z₂ = -4i, and z₃ = 5, show that
(i) (z₁ + z₂) + z₃ = z₁ + (z₂ + z₃)
Solution:
z₁ = 1 – 3i, z₂ = -4i, z₃ = 5
(z₁ + z₂) + z₃
= (1 – 3i – 4i) + 5
= (1 – 7i) + 5
= 6 – 7i …… (1)
z₁ + (z₂ + z₃)
= (1 – 3i) + (-4i + 5)
= 6 – 7i ……. (2)
from (1) & (2) we get
∴ (z₁ + z₂) + z₃ = z₁ + (z₂ + z₃)

(ii) (z₁ z₂)z₃ = z₁(z₂ z₃)
Solution:
(z₁ z₂) z₃ = [(1 – 3i) (-4i]5
= [-4i + 12 i²]5
= [-12 – 4i] 5
= -60 – 20i ……. (1)
z₁ (z₂ z₃) = (1 – 3i)[(-4i)(5)]
= (-20i + 60 i²)
= -20i – 60 ……. (2)
from (1) & (2) we get
∴ (z₁ z₂)(z₃) = z₁ (z₂ z₃)

Question 2.
If z₁ = 3, z₂ = 7i, and z₃ = 5 + 4i, show that
(i) z₁(z₂ + z₃) = z₁ z₂ + z₁ z₃
Solution:
z₁ = 3, z₂ = 7i, z₃ = 5 + 4i
z₂ + z₃ = -7i + 5 + 4i
= 5 – 3i
z₁ (z₂ + z₃) = 3 (5 – 3i) + 15 – 9i …………. (1)
z₁ z₂ = 3(-7i) = -21i
z₁ z₃ = 3(5 + 4i) = 15 + 12i
z₁ z₂ + z₁ z₃ = -21i + 15 + 12i
= 15 – 9i ……… (2)
∴ from 1 and 2
z₁(z₂ + z₃) = z₁ z₂ + z₁ z₃
Hence proved.

(ii) (z₁ + z₂)z₃ = z₁ z₃ + z₂ z₃
Solution:
z₁ + z₂ = 3 – 7i
(z₁ + z₂)z₃ = (3 – 7i) (5 + 4i)
= 15 + 12i – 35i + 28i²
= 15 + 12i – 35i + 28i
= 43 – 23i ………… (1)
z₁ z₃ = 3(5 + 4i) = 15 + 12i
z₂ z₃ = – 7i(5 + 4i) = -35i – 28i²
= – 35i + 28
z₁ z₃ + z₂ z₃ = (15 + 12i) + (-35i + 28)
= 15 + 12i – 35i + 28
= 43 – 23i …………. (2)
∴ from 1 and 2
(z₁ + z₂)z₃ = z₁ z₃ + z₂ z₃
Hence proved.

Question 3.
If z₁ = 2 + 5i, z₂ = – 3 – 4i, and z₃ = 1 + i, find the additive and multiplicative inverse of z₁, z₂ and z₃.
Solution:
(i) z₁ = 2 + 5i
additive inverse z₁ is -z₁
⇒ -(2 + 5i) = -2 – 5i
Multiplicative inverse z₁ is (z₁)^-1
We know
z₁ z₁^-1 = 1
⇒ (2 + 5i) (u + iv) = 1 [∵ z^-1 = u + iv]
2u + 2iv + 5iu – 5v = 1
(2u – 5v) + i (5u + 2v) = 1 + i 0
Equating real and imaginary parts
2u – 5v = 1
5u + 2v = 0
Solving them, we get

(ii) z₂ = – 3 – 4i
Additive inverse z₂ is -z₂
⇒ -(3 – 4i) = 3 + 4i
Multiplicative inverse z₂ is (z₂)^-1
We know
z₂ z₂^-1 = 1
⇒ (-3 – 4i) (u + iv) = 1 [∵ z₂^-1 = u + iv]
-3u – 3iv – 4iu + 4v = 1
(-3u + 4v) + i (-4u – 3v) = 1 + i 0
we get -3u + 4v = 1
-4u – 3v = 0

(iii) z₃ = 1 + i
(а) Additive inverse of z₃ = -z₃ = -(1 + i) = -1 – i
(b) Multiplicative inverse of
\(z_{3}=\frac{1}{z_{3}} \frac{1}{1+i} \times \frac{1-i}{1-i}=\frac{1-i}{2}\)

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Maths Guide Pdf Chapter 2 Complex Numbers Ex 2.1 Textbook Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Maths Solutions Chapter 2 Complex Numbers Ex 2.1

Question 1.
i¹⁹⁴⁷ + i¹⁹⁵⁰
Solution:
i¹⁹⁴⁷ + i¹⁹⁵⁰ = (i⁴)⁴⁸⁶ i³ + (i⁴)⁴⁸⁷ i²
[∵ i² = -1; i³ = i; i⁴ = 1]
= (1)⁴⁸⁶ (-i) + (1)⁴⁸⁷ (-1)
= – i – 1 = -(1 + i)

Question 2.
i¹⁹⁴⁸ – i^-1869
Solution:
= (i⁴)⁴⁸⁷ – [(i⁴)⁴⁶⁷ i¹]^-1
= (1)⁴⁸⁷ – (i)^-1 = 1 – \(\frac{1}{i}\) = 1 + i

Question 3.
\(\sum_{n=1}^{12} i^{n}\)
Solution:
= i¹ + i² + i³ + i⁴ + …. + i¹²
= (i – 1 – i + 1) + (i – 1 – i + 1) + (i – 1 – i + 1)
= 0

Question 4.
i⁵⁹ + \(\frac{1}{i^{59}}\)
Solution:
(-i) + \(\frac{1}{(-i)}\)
[∵ i⁵⁹ = i⁵⁶ i³ = (i⁴)¹⁴ (-i) = 1(-i) = -i]
= -i + i = 0

Question 5.
i i² i³ …… i²⁰⁰⁰
Solution:
= i^1+2+3+2000
[∵ 1 + 2 + 3 + …….. n = \(\frac{n(n+1)}{2}\)]
= i^{(\(\frac{2000×2001}{2}\))}
= i^(1000×2001)
= [i¹⁰⁰⁰]²⁰⁰¹
= i^2001000
= 1

Question 6.
\(\sum_{n=1}^{10} i^{n+50}\)
solution:
= i⁵¹ + i⁵² + i⁵³ + ……. + i⁶⁰
= i³ + i⁴ +i + i² + ……. + i⁴
= -i + 1 + i – 1 – i + 1 + i – 1 – i + 1
= 1 – i

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Maths Guide Pdf Chapter 2 Complex Numbers Ex 2.2 Textbook Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Maths Solutions Chapter 2 Complex Numbers Ex 2.2

Question 1.
Evaluate the following if z = 5 – 2i and w = -1 + 3i
(i) z + w
Solution:
z = 5 – 2i, w = -1 + 3i
z + w = (5 – 2i) + (-1 + 3i)
= (5 – 1) + (-2i + 3i)
= 4 + i

(ii) z – iw
Solution:
z – iw = (5 – 2i) – i (-1 + 3i)
= 5 – 2i + i + 3
= (5 + 3) + (-2i + i)
= 8 – i

(iii) 2z + 3w
Solution:
2z + 3w = 2(5 – 2i) + 3 (-1 +3i)
= 10 – 4i – 3 + 9i
= 7 + 5 i

(iv) zw
Solution:
zw = (5 – 2i) (-1 + 3i)
= -5 + 15i + 2i – 6i²
= -5 + 17i + 6
= 1 + 17i

(v) z² + 2zw + w²
Solution:
= (z + w)² [from (i)]
= (4 + i)²
= 16 – 1 + 8i
= 15 + 8i

(vi) (z + w)²
Solution:
(vi) (z + w)² = 15 + 8z [from (v)]

Question 2.
Given the complex number z = 2 + 3i, represent the complex numbers in the Argand diagram.
(i) z = 2 + 3i
iz = i(2 + 3i)
= (2i – 3)
= -3 + 2i
z + iz = (2 + 3i) + (-3 + 2i)
= -1 + 5i

(ii) z, – iz and z – iz
z = 2 + 3i
-iz = -i (2 + 3i)
= -2i – 3i² = -2i + 3
= 3 – 2i
z- iz= 2 + 3i -3 + 2i
= 5 + i

Question 3.
Find the values of the real numbers x and y. if the complex numbers
(3 – i)x – (2 – i) y + 2i + 5 and 2x + (-1 + 2i)y + 3 + 2i are equal.
Solution:
(3 – i) x – (2 – i) y + 2i + 5 = 2x + (-1 + 2i) y + 3 + 2i
⇒ 3x – ix – 2y + iy + 2i + 5 = 2x – y + 2yi + 3 + 2i
⇒ (3x – 2y + 5) + 1 (-x + y + 2) = (2x – y + 3) + i (2y + 2)
Equate real parts on both sides
3x – 2y + 5 = 2x – y + 3
x – y = -2 ……. (1)
Equate imaginary parts on both sides
-x + y + 2 = 2y + 2
-x – y = 0
x + y = 0 ……. (2)
(1) + (2) ⇒ 2x = -2
x = -1
Substituting x = -1 in (2)
-1 + y = 0
⇒ y = 1
∴ x = -1, y = 1

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Maths Guide Pdf Chapter 1 Applications of Matrices and Determinants Ex 1.8 Textbook Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Maths Solutions Chapter 1 Applications of Matrices and Determinants Ex 1.8

Choose the Most Suitable Answer.

Question 1.
If |adj(adj A) |=| A|⁹, then the order of the square matrix A is:
(a) 3
(b) 4
(c) 2
(d) 5
Solution:
(b) 4
Hint:
Since |adj(adj A)| = |A|^{(n – 1)2}
(n – 1)² = 9 = 3²
n – 1 = 3
n = 4

Question 2.
If A is a 3 × 3 non-singular matrix such that AA^T = A^T A and B = A^-1A^T, then BB^T =
(a) A
(b) B
(C) I₃
(d) B^T
Solution:
(C) I
Hint:
AA^T = A^TA and B = A^-1A^T
B^T = (A^-1)^T(A^T)^T = (A^-1)^T A
BB^-1 = (A^-1 A^T) (A^-1)^T A = A^-1 (AA^-1)^T A
= A^-1 (I)^T A = A^-1 A = I₃

Question 3.
If A = \(\begin{bmatrix} 3 & 5 \\ 1 & 2 \end{bmatrix}\) B = adj A and C = 3A, then \(\frac{|adj B|}{|C|}\) =
(a) \(\frac{1}{3}\)
(b) \(\frac{1}{9}\)
(C) \(\frac{1}{4}\)
(d) 1
Solution:
(a) \(\frac{1}{3}\)
Hint:

Question 4.
If A \(\begin{bmatrix} 1 & -2 \\ 1 & 4 \end{bmatrix}\) = \(\begin{bmatrix} 6 & 0 \\ 0 & 6 \end{bmatrix}\), then A:

Solution:
(c) \(\begin{bmatrix} 4 & 2 \\ -1 & 1 \end{bmatrix}\)
Hint:

Solve the equations we get
a = 4, b = 2, c = -1, d = 1
A = \(\begin{bmatrix} 4 & 2 \\ -1 & 1 \end{bmatrix}\)

Question 5.
If A = \(\begin{bmatrix} 7 & 3 \\ 4 & 2 \end{bmatrix}\) then 9I₂ – A =
(a) A^-1
(b) \(\frac{A^{-1}}{2}\)
(c) 3A^-1
(d) 2A^-1
Solution:
(d) 2A^-1
Hint:
|A| = 14 – 12 = 2

Question 6.
If A = \(\begin{bmatrix} 2 & 0 \\ 1 & 5 \end{bmatrix}\) and B = \(\begin{bmatrix} 1 & 4 \\ 2 & 0 \end{bmatrix}\) then |adj (AB)| =
(a) -40
(b) -80
(c) -60
(d) -20
Solution:
(b) -80
Hint:

∴ |adj (AB)| = 8 – 88 = -80

Question 7.
If P = \(\left[ \begin{matrix} 1 & x & 0 \\ 1 & 3 & 0 \\ 2 & 4 & -2 \end{matrix} \right] \) is the adjoint of 3 × 3 matrix A and |A| = 4, then x is
(a) 15
(b) 12
(c) 14
(d) 11
Solution:
(d) 11
Hint:
Since |adj A| = |A|^{n – 1} (n = 3)
1(-6 + 0) – x(-2) = 4²
-6 + 2x = 16
2x = 16 + 6 = 22
x = 11

Question 8.

(a) 0
(b) -2
(c) -3
(d) -1
Solution:
(d) -1
Hint:

Question 9.
If A, B and C are invertible matrices of some order, then which one of the following is not true?
(a) adj A = |A|A^-1
(b) adj (AB) = (adj A)(adj B)
(c) det A^-1 = (det A)^-1
(d) (ABC)^-1 = C^-1B^-1A^-1
Solution:
(b) adj (AB) = (adj A)(adj B)
Hint:
adj (AB) ≠ (adj A)(adj B)

Question 10.

Solution:
(a) \(\begin{bmatrix} 2 & -5 \\ -3 & 8 \end{bmatrix}\)
Hint:
(AB)^-1 = B^-1 A^-1
(AB)^-1 A = B^-1 [A^-1]A
(AB)^-1 A = B^-1
(A^-1)^-1 = A
|A^-1| = 3 – 2 = 1

Question 11.
If A^TA^-1 is symmetric, then A² =
(a) A^-1
(b) (A^T)²
(c) A^T
(d) (A^-1)²
Solution:
(b) (A^T)²
Hint:
(A^T A^-1)^T = A^T A^-1
(A^-1)^T (A^T)^T = A^T A^-1
(A^-1)^T A = A^T A^-1
A^T (A^-1)^T AA = (A^T) A^T A^-1 A
(pre and post multiply by A^T and A)
A² = (A^T)²

Question 12.
If A is a non-singular matrix such that A^-1 = \(\begin{bmatrix} 5 & 3 \\ -2 & -1 \end{bmatrix}\), then (AT)^-1 =

Solution:
(d) \(\begin{bmatrix} 5 & -2 \\ 3 & -1 \end{bmatrix}\)
Hint:
A^-1 = \(\begin{bmatrix} 5 & 3 \\ -2 & -1 \end{bmatrix}\)
Since (A^T)^-1 = (A^-1)^T = \(\begin{bmatrix} 5 & -2 \\ 3 & -1 \end{bmatrix}\)

Question 13.

(a) \(\frac{-4}{5}\)
(b) \(\frac{-3}{5}\)
(c) \(\frac{3}{5}\)
(d) \(\frac{4}{5}\)
Solution:
(a) \(\frac{-4}{5}\)
Hint:
Since A^T = A^-1
AA^T =  I

Question 14.

(a) (cos² \(\frac{θ}{2}\))A
(b) (cos² \(\frac{θ}{2}\))A^T
(c) (cos²θ)I
(d) (sin² \(\frac{θ}{2}\))A
Solution:
(b) (cos² \(\frac{θ}{2}\))A^T
Hint:

Question 15.

(a) 0
(b) sin θ
(c) cos θ
(d) 1
Solution:
(d) 1
Hint:

cos² θ + sin² θ = k
Hence k = 1

Question 16.
If A = \(\begin{bmatrix} 2 & 3 \\ 5 & -2 \end{bmatrix}\) be such that λA^-1 = A, then λ is:
(a) 17
(b) 14
(c) 19
(d) 21
Solution:
(c) 19
Hint:
λA^-1 = A

⇒ λ = 19

Question 17.
If adj A = \(\begin{bmatrix} 2 & 3 \\ 4 & 1 \end{bmatrix}\) and adj B = \(\begin{bmatrix} 1 & -2 \\ -3 & 1 \end{bmatrix}\) then adj (AB) is:

Solution:
(b) \(\begin{bmatrix} -6 & 5 \\ -2 & -10 \end{bmatrix}\)
Hint:
adj (AB) = (adj B) (adj A)

Question 18.

(a) 1
(b) 2
(c) 4
(d) 4
Solution:
(a) 1
Hint:

∴ Number of non zero row = 1
ρ(A) = 1

Question 19.

(a) \(e^{(Δ_{2}/Δ_{1})}\), \(e^{(Δ_{3}/Δ_{1})}\)
(b) log(Δ₁/Δ₃), log(Δ₂/Δ₃)
(c) log(Δ₂/Δ₁), log(Δ₃/Δ₁)
(d) \(e^{(Δ_{1}/Δ_{3})}\), \(e^{(Δ_{2}/Δ_{3})}\)
Solution:
(d) \(e^{(Δ_{1}/Δ_{3})}\), \(e^{(Δ_{2}/Δ_{3})}\)
Hint:
x^ay^b = e^m
a log x + b log y = m
x^cy^d = eⁿ
c log x + d log y = n

Question 20.
Which of the following is/are correct?
(i) Adjoint of a symmetric matrix is also a symmetric matrix.
(ii) Adjoint of a diagonal matrix is also a diagonal matrix.
(iii) If A is a square matrix of order n and λ is a scalar, then adj(λA) = λⁿ adj (A).
(iv) A(adj A) = (adj A)A = |A|I
(a) Only (i)
(b) (ii) and (iii)
(c) (iii) and (iv)
(d) (i), (ii) and (iv)
Solution:
(d) (i), (ii) and (iv)

Question 21.
If ρ(A) ρ([A | B]), then the system AX = B of linear equations is:
(a) consistent and has a unique solution
(b) consistent
(c) consistent and has infinitely many solutions
(d) inconsistent
Solution:
(b) consistent
Hint:
If ρ(A) = ρ[A|B] = no. of unknowns
We say consistent an unique solutions
Hence ρ(A) = ρ[A|B] ← given

Question 22.
If 0 ≤ θ ≤ π and the system of equations x + (sin θ)y – (cos θ)z = 0, (cos θ) x – y + z = 0, (sin θ) x + y + z = 0 has a non-trivial solution then θ is:
(a) \(\frac{2π}{3}\)
(b) \(\frac{3π}{4}\)
(c) \(\frac{5π}{6}\)
(d) \(\frac{π}{4}\)
Solution:
(d) \(\frac{π}{4}\)
Hint:
If AX = 0 has non  trivial solution if |A| = 0

⇒ 1(1 – 1) – sinθ (-cosθ – sinθ) – cosθ (cosθ + sinθ) = 0
⇒ + sinθ cosθ + sin²θ – cos²θ – sinθ cosθ = 0
⇒ sin²θ – cos²θ = 0
⇒ sinθ = cosθ
θ =\(\frac{π}{4}\)

Question 23.

(a) λ = 7, µ ≠ -5
(b) λ = -7, µ = 5
(c) λ ≠ 7, µ ≠ -5
(d) λ = 7, µ = -5
Solution:
(d) λ = 7, µ = -5
Hint:
ρ(A) = ρ[A | B] = 2
λ – 7 = 0 and µ + 5 = 0
λ = 7, µ = -5

Question 24.

(a) 2
(b) 4
(c) 3
(d) 1
Solution:
(b) 4
Hint:
B = A^-1

Question 25.

Solution:
(a) \(\left[\begin{array}{rrr}
3 & -3 & 4 \\
2 & -3 & 4 \\
0 & -1 & 1
\end{array}\right]\)
Hint:
adj (adj A) = |A|^n-2 A = |A|² A
|A|= 3(-3 + 4) + 3(2) + 4 (-2)
= 3 + 6 – 8
= 1

Students can download Maths Chapter 6 Trigonometry Unit Exercise 6 Questions and Answers, Notes, Samacheer Kalvi 10th Maths Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Maths Solutions Chapter 6 Trigonometry Unit Exercise 6

Question 1.
Prove that
(i) cot² A \(\left(\frac{\sec A-1}{1+\sin A}\right)\) + sec² A \(\left(\frac{\sin A-1}{1+\sec A}\right)\) = 0
(ii) \(\frac{\tan ^{2} \theta-1}{\tan ^{2} \theta+1}\) = 1 – 2 cos² θ
Answer:


Hence it is proved

= 1 – cos² θ
L.H.S = R.H.S
Hence it is proved.

Question 2.
Prove that
\(\left(\frac{1+\sin \theta-\cos \theta}{1+\sin \theta+\cos \theta}\right)^{2}=\left(\frac{1-\cos \theta}{1+\cos \theta}\right)\)
Answer:

LHS = RHS
Hence it is proved

Question 3.
If x sin² θ + y cos² θ = sin θ cos θ and x sin θ = y cos θ, then prove that x² + y² = 1.
Answer:
Given x sin² θ + y cos² θ = sin θ cos θ
x sin θ = y cos θ ……..(1)
x sin³ θ + y cos³ θ = sin θ cos θ
x sin θ (sin² θ) + y cos θ (cos² θ) = sin θ cos θ
x sin θ (sin² θ) + x sin θ (cos² θ) = sin θ cos θ
x sin θ (sin² θ + cos² θ) = sin θ cos θ
x sin θ = sin θ cos θ
x = cos θ
substitute x = cos θ in (1)
cos θ sin θ = y cos θ y = sin θ
L. H. S = x² + y² = cos² θ + sin² θ = 1
L.H. S = R.H.S
Hence it is proved.

Question 4.
If a cos θ – b sin θ = c, then prove that (a sin θ + b cos θ) = ± \(\sqrt{a^{2}+b^{2}-c^{2}}\).
Answer:
Given a cos θ – b sin θ = c
Squaring on both sides
(a cos θ – b sin θ)² = c²
a² cos² θ + b² sin² θ – 2 ab cos θ sin θ = c²
a² (1 – sin² θ) + b² (1 – cos² θ) – 2 ab cos θ sin θ = c²
a² – a² sin² θ + b² – b² cos² θ – 2 ab cos θ sin θ = c²
– a² sin² θ – B² – cos² θ – 2 ab cos θ sin θ = – a² – b² + c²
a² sin² θ + b² cos² θ + 2 ab cos θ sin θ = a² + b² – c²
(a sin θ + b cos θ)² – a² + b² – c²
a sin θ + b cos θ = ± \(\sqrt{a^{2}+b^{2}-c^{2}}\)
Hence it is proved.

Question 5.
A bird is sitting on the top of a 80 m high tree. From a point on the ground, the angle of elevation of the bird is 45° . The bird flies away horizontally in such away that it remained at a constant height from the ground. After 2 seconds, the angle of elevation of the bird from the same point is 30° . Determine the speed at which the bird flies. (\(\sqrt { 3 }\) = 1.732)
Answer:

A is the initial position of the bird B is the final position of the bird Let the speed of the bird be “s”
Distance = speed × time
∴ AB = 2x
Let CD be x
∴ CE = x + 2s
In the ∆ CDA, tan 45° = \(\frac { AD }{ CD } \)
1 = \(\frac { 80 }{ x } \)
x = 80 ……..(1)
In the ∆ BCE
tan 30° = \(\frac { BE }{ CE } \)
\(\frac{1}{\sqrt{3}}\) = \(\frac { 80 }{ x+2s } \)
x + 2s = 80 \(\sqrt { 3 }\)
x = 80 \(\sqrt { 3 }\) – 2 s ………(2)
From (1) and (2) we get
80 \(\sqrt { 3 }\) – 2 s = 80
80 \(\sqrt { 3 }\) – 80 = 2 s ⇒ 80 (\(\sqrt { 3 }\) – 1) = 2 s
s = \(\frac{80(\sqrt{3}-1)}{2}\) = 40 (1.732 – 1) = 40 × 0.732 = 29.28
Speed of the flying bird = 29.28 m/sec

Question 6.
An aeroplane is flying parallel to the Earth’s surface at a speed of 175 m/sec and at a height of 600 m. The angle of elevation of the aeroplane from a point on the Earth’s surface is 37° at a given point. After what period of time does the angle of elevation increase to 53°? (tan 53° = 1.3270, tan 37° = 0.7536)
Answer:
Let C is the initial and D is the final position of the aeroplane.
Let the time taken by the aeroplane be “t”
∴ CD = 175 t (Distance = speed × time)

Let AB be x
∴ AE = x + 175 t
In the right ∆ ABC


∴ Time taken is 1. 97 seconds

Question 7.
A bird is flying from A towards B at an angle of 35°, a point 30 km away from A. At B it changes its course of flight and heads towards C on a bearing of 48° and distance 32 km away.
(i) How far is B to the North of A?
(ii) How far is B to the West of A?
(iii) How far is C to the North of B?
(iv) How far is C to the East of B?
(sin 55° = 0.8192, cos 55° = 0.5736, sin 42° = 0.6691, cos 42° = 0.7431)
Answer:

(i) To find the distance of B to the north of A
In ∆ ABB,

Distance of B to the North of A = 24. 58 km

(ii) Distance from B to the west of A is AB’
In ∆ ABB’
cos 55° = \(\frac{\mathrm{AB}^{\prime}}{\mathrm{AB}}\)
0.5736 = \(\frac{A B^{\prime}}{30}\)
∴ AB’ = 0.5736 × 30 = 17. 21 km
Distance of B to the West of A is 17. 21 km

(iii) Distance from C to the North of B is CD
In the right ∆ BCD, sin 42° = \(\frac { CD }{ BC } \)
0.6691 = \(\frac { BD }{ 32 } \)
∴ CD = 0.6691 × 32 = 21.41 km
Distance of C to the North B is 21. 41 km

(iv) The distance of C to the East of B is BD
In the right ∆ BDC, cos 42° = \(\frac { BD }{ BC } \)
0.7431 = \(\frac { BD }{ 32 } \)
∴ BD = 0.7431 × 32
= 23.78 km
Distance of C to the East of B is 23.78 km.

Question 8.
Two ships are sailing in the sea on either side of the lighthouse. The angles of depression of two ships as observed from the top of the lighthouse are 60° and 45° respectively. If the distance between the ships is 200 \(\left(\frac{\sqrt{3}+1}{\sqrt{3}}\right)\) meters, find the height of the lighthouse
Answer:
Let A and B the position of the first ship and the second ship
Distance = 200 \(\left(\frac{\sqrt{3}+1}{\sqrt{3}}\right)\) m
Let the height of the light house CD be “h”

In the right ∆ ACD, tan 60° = \(\frac { CD }{ AD } \)
\(\sqrt { 3 }\) = \(\frac { h }{ AD } \)
∴ AD = \(\frac{h}{\sqrt{3}}\) ……….(1)
In the right ∆ BCD
tan 45° = \(\frac { DC }{ BD } \)
1 = \(\frac { h }{ BD } \)
∴ BD = h
Distance between the two ships = AD + BD
200 (\(\frac{\sqrt{3}+1}{\sqrt{3}}\)) = \(\frac{h}{\sqrt{3}}\) + h ⇒ 200 (\(\sqrt { 3 }\) + 1) = h + \(\sqrt { 3 }\) h
200 (\(\sqrt { 3 }\) + 1) = h(1 + \(\sqrt { 3 }\)) ⇒ h = \(\frac{200(\sqrt{3}+1)}{(1+\sqrt{3})}\)
h = 200
Height of the light house = 200 m

Question 9.
A building and a statue are in opposite side of a street from each other 35 m apart. From a point on the roof of building the angle of elevation of the top of statue is 24° and the angle of depression of base of the statue is 34° . Find the height of the statue. (tan 24° = 0.4452, tan 34° = 0.6745)
Answer:
Let the height of the statue be “h” m
Let AD be x
∴ EC = h – x
In the right ∆ ABD,

tan 34° = \(\frac { AD }{ AB } \)
0.6745 = \(\frac { x }{ 35 } \)
∴ x = 0.6745 × 35 ⇒ x = 23.61 m
In the right ∆ DEC ⇒ tan 24° = \(\frac { EC }{ DE } \)
0.4452 = \(\frac { h-x }{ 35 } \) ⇒ h – x = 0.4452 × 35
h – 23.61 = 15. 58 ⇒ h = 15.58 + 23.61 = 39.19 m
Height of the statue = 39.19 m

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Maths Guide Pdf Chapter 1 Applications of Matrices and Determinants Ex 1.7 Textbook Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Maths Solutions Chapter 1 Applications of Matrices and Determinants Ex 1.7

Question 1.
Solve the following system of homogeneous equations.
(i) 3x + 2y + 7z = 0; 4x – 3y – 2z = 0; 5x + 9y + 23z = 0
Solution:

ρ(A) = 2 ρ[A | B] = 2
ρ(A) ρ[A | B] = 2 < n
The system is consistent. It has non trivial solution.
Writing the equivalent equations from echelon form
3x + 2y + 7z = 0 ………… (1)
-17y – 34z = 0 ……….. (2)
Put z = t
(2) ⇒ -17y = 34t
y = \(\frac {34t}{-17}\) = -2t
(1) ⇒ 3x + 2(-2t) + 7t = 0
3x – 4t + 7t = 0
3x + 3t = 0
3x = -3t
x = -t
(x, y, z) (-t, -2t, t) ∀ t ∈ R

(ii) 2x + 3y – z = 0, x – y – 2z = 0, 3x + y + 3z = 0
Solution:

ρ(A) = 3 ρ[A | B] = 3
ρ(A) = ρ[A | B] = 3
The system is consistent. It has trivial solution.
x = 0, y = 0, z = 0

Question 2.
Determine the values of λ for which the following system of equations.
x + y + 3z = 0; 4x + 3y + λz = 0, 2x + y + 2z = 0 has
(i) a unique solution
(ii) a non-trivial solution.
Solution:

Case (i):
if λ ≠ 8
ρ(A) = 3 ρ(A | B) = 3
ρ(A) = ρ(A | B) = 3 = n
The system is consistent. It has unique (trivial) solution.
∴ Solution x = 0, y = 0, z = 0

Case (ii):
if λ = 8
ρ(A)= ρ(A | B) = 2
ρ(A) = ρ(A | B) = 2 < n
The system is consistent. It has non trivial solution.

Question 3.
By using Gaussian elimination method, balance the chemical -reaction equation:
C₂H₆ + O₂ → H₂O + CO₂.
Solution:
We are searching for positive integers x₁, x₂, x₃ and x₄
x₁ C₂H₆ + x₂ O₂ → x₃ H₂O + x₄ CO₂ ……….(1)
The number of carbon atoms on the LHS of (1) should be equal to the number of carbon atoms on the RHS of (1) so we get a linear
homogeneous equation.
2x₁ x₄ = 2x₁ – x₄ = 0 ……..(2)
6x₁ = 2x₃ = 6x₁ – 2x₃ = 0
÷ 2 ⇒ 3x₁ – x₃ = 0 ………(3)
2x₂ = x₃ + 2x₄ ⇒ 2x₂ – x₃ – 2x₄ = 0 ……… (4)
Equation (2), (3) and (4) constitute a homogeneous system of linear equations in four unknowns.
Augmented matrix

The system is consistent and has an infinite number of solutions.
Writing the equations using the echelon form we get
-2x₃ + 3x₄ = 0 ……….. (1)
2x₂ – x₃ – 2x₄ = 0 ………… (2)
2x₁ – x₄ = 0 …………. (3)
Put x₄ = t
(3) ⇒ 2x₁ – t = 0
x₁ = \(\frac {t}{2}\)
(1) ⇒ -2x₃ + 3x₄ = 0
-2x₃ = -3t
x₃ = \(\frac {3}{2}\) t
(2) ⇒ 2x₂ – x₃ – 2x₄ = 0
2x₂ – \(\frac {3}{2}\) t – 2t = 0
2x₂ = \(\frac {3}{2}\) t + 2t = \(\frac {7t}{2}\)
x₂ = \(\frac {7t}{4}\)
(x₁, x₂, x₃, x₄) = (\(\frac {t}{2}\), \(\frac {7t}{4}\), \(\frac {3}{2}\)t, t) ∀ t ∈ R
since x₁, x₂, x₃ and x₄ are positive integers.
Let us choose t = 4

So the balanced equation is
2C₂H₆ + 7O₂ → 6H₂O + 4CO₂.