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LIGHT WAVES
OBJECTIVE-I
1. Light is
(a) wave phenomenon
(b) particle phenomenon
(c) both particle and wave phenomenon.
ANSWER: (c)
EXPLANATION: The photoelectric effect shows it as a particle phenomenon while the interference and diffraction of light shows it as a wave phenomenon. Hence duel nature.
2. The speed of light depends on
(a) on elasticity of the medium only
(b) on inertia of the medium only
(c) on elasticity as well as inertia
(d) neither on elasticity nor on inertia
ANSWER: (d)
EXPLANATION: The light does not require even a medium. The speed of light in a medium is the intrinsic property of that medium which is related to the refractive index of the medium.
3. The equation of a light wave is written as
y = A sin(kx-⍵t).
Here y represents
(a) displacement of ether particles
(b) pressure in the medium
(c) density of the medium
(d) electric field.
ANSWER: (d)
EXPLANATION: The light wave does not require a medium, hence the displacement of particles, the variation of pressure and density in the medium has no relation to the light wave. Light is an electromagnetic wave in which the electric field transverse to the motion of wave changes with time and place. Here y represents the electric field in the wave equation.
4. Which of the following properties show that light is a transverse wave?
(a) Reflection.
(b) Interference.
(c) Diffraction.
(d) Polarization.
ANSWER: (d)
EXPLANATION: The reflection, interference and diffraction effects are shown by both transverse and longitudinal waves. But polarization is only possible with a transverse wave because the transverse displacement of the particles of a medium or the transverse change of the electric field (as in lightwave) are in a plane and a slit perpendicular to this plane will not allow it to pass.
5. When light is refracted into a medium,
(a) its frequency and wavelength both increase
(b) its wavelength increases but frequency remains unchanged
(c) its wavelength decreases but frequency remains unchanged
(d) its wavelength and frequency both decrease.
ANSWER: (c)
EXPLANATION: When light is refracted into a medium its speed changes but the frequency remains the same because the energy associated with a photon of this light is proportional to the frequency of the light and it remains unchanged. Since the wavelength 𝜆 = c/𝜈, i.e. 𝜆 ∝ c. So the wavelength changes. Option (c) is true.
6. When light is refracted, which of the following does not change?
(a) wavelength.
(b) frequency.
(c) velocity.
(d) amplitude.
ANSWER: (b)
EXPLANATION: Same explanation as in question above.
7. The amplitude modulated (AM) radio wave bends appreciably round the corners of 1 m x 1 m board but frequency modulated (FM) wave only negligibly bends. If the average wavelengths of AM and FM waves are 𝜆ₐ and 𝜆ᵩ,
(a) 𝜆ₐ > 𝜆ᵩ
(b) 𝜆ₐ = 𝜆ᵩ
(c) 𝜆ₐ < 𝜆ᵩ
(d) we don't have sufficient information to decide about the relation of 𝜆ₐ and 𝜆ᵩ.
ANSWER: (a)
EXPLANATION: The wave having greater wavelength will bend more.
In fact, the frequency of the FM waves is nearly 100 times more than the AM waves hence the wavelength of the AM waves is 100 times more than FM waves.
8. Which of the following sources gives the best monochromatic light?
(a) A candle
(b) A bulb
(c) A mercury tube
(d) A laser.
ANSWER: (d)
EXPLANATION: The candle, bulb and mercury tube give lights of a mixture of wavelengths. In a laser, the same wavelength of light is processed and amplified. Hence the option (d).
9. The wavefronts of a light wave traveling in the vacuum are given by x+y+z = c. The angle made by the direction of propagation of light with X-axis is
(a) 0°
(b) 45°
(c) 90°
(d) cos⁻¹(1/√3).
ANSWER: (d)
EXPLANATION: The given equation of the wavefronts represent a plane that intersects each of the axes at a distance c from the origin. Let these points be named A, B and C. ABC is an equilateral triangle of side c.
Diagram for Q-9
The direction of propagation of light will be normal to the plane. In this case, the normal makes equal angles with each of the axes say α. Since the sum of the squares of the direction cosines equals one, here for the normal
cos²α+cos²α+cos²α = 1
→3 cos²α = 1
→cos²α = 1/3
→cos α = 1/√3
→α = cos⁻¹ (1/√3)
Hence the option (d).
10. The wavefronts of light coming from a distant source of unknown shape are nearly
(a) plane
(b) elliptical
(c) cylindrical
(d) spherical.
ANSWER: (a)
EXPLANATION: The wavefronts of light coming from a distant source are nearly plane because at a large distance the curve is magnified and a small portion of it is nearly plane.
11. The inverse square law of intensity (i.e. intensity ∝ 1/r²) is valid for a
(a) point source
(b) line source
(c) plane source
(d) cylindrical source.
ANSWER: (a)
EXPLANATION: Only for a point source the intensity can be written as I = E/4πr², where E is the strength of the source. Hence
E ∝ 1/r².
12. Two sources are called coherent if they produce waves
(a) of equal wavelength
(b) of equal velocity
(c) having same shape of wavefront
(d) having a constant phase difference.
ANSWER: (d)
EXPLANATION: By definition, the two sources are called coherent if the initial phase difference does not change with time i.e. the phase difference remains constant.
13. When a drop of oil is spread on a water surface, it displays beautiful colors in daylight because of
(a) dispersion of light
(b) reflection of light
(c) polarization of light
(d) interference of light
ANSWER: (d)
EXPLANATION: The drop of oil spreads on the water surface and makes a thin film. When the daylight is incident on the upper surface of the film, a part is reflected in the air while another is transmitted and falls on the inner surface. Here again, the light is reflected and transmitted in parts. The reflected light goes through this process multiple times and these multiple reflected rays have path differences and interfere with each other. If the following condition fulfilled for a certain wavelength, then this color is illuminated and display beautiful colors.
2µd = (n+½)𝜆
where d = thickness of the film and 𝜆 = wavelength of a certain color.
14. Two coherent sources of different intensities send waves which interfere. The ratio of maximum intensity to the minimum intensity is 25. The intensities of the sources are in the ratio
(a) 25:1
(b) 5:1
(c) 9:4
(d) 625:1
ANSWER: (c)
EXPLANATION: Since the resultant field at a point is given as
E₀² = E₁² + E₂² + 2E₁E₂ cos𝛿
Where E₁ and E₂ = amplitudes of interfering waves and 𝛿 is phase difference. For maximum amplitude cos𝛿 = 1 and for the minimum cos𝛿 = -1, hence maximum amplitude is given as
E₀² = (E₁ + E₂)²
and the minimum amplitude as
E₀'² = (E₁ - E₂)²
Since the intensity is proportional to the square of the amplitude, hence the maximum intensity
I = (√I₁ + √I₂)²
and the minimum intensity
I' = (√I₁ - √I₂)²
Let I₁ = k I₂
Hence, I = (√k+1)² I₂
and I' = (√k - 1)² I₂
Given, I/I' = 25
→(√k+1)²/(√k-1)² = 25
→√k + 1 = 5√k - 5
→4√k = 6
→√k =6/4 = 3/2
→k = 9/4
Hence the intensities of the sources are in the ratio 9:4.
15. The slits in a Young's double slit experiment have equal width and the source is placed symmetrically with respect to the slits. The intensity at the central fringe is I₀. If one of the slits is closed, the intensity at this point will be
(a) I₀
(b) I₀/4
(c) I₀/2
(d) 4I₀
ANSWER: (b)
EXPLANATION: As in the previous explanation the maximum intensity
I₀ = (√I₁ + √I₂)². Here given that I₁ = I₂ = I (say).
→I₀ = 4 I ------- (i)
If one slit is closed I₀' = I
→I₀' = I₀/4 {from (i)}
Hence option (b)
16. A thin transparent sheet is placed in front of a Young's double slit. The fringe width will
(a) increase
(b) decrease
(c) remain same
(d) become non-uniform
ANSWER: (c)
EXPLANATION: The fringe width is given as
w = D𝜆/d
where D = distance of the screen from the slits
d = distance of slits.
The wavelength 𝜆 remains the same when the light comes out of the film. Thus none of the entity D, d or 𝜆 changes. So the fringe with will remain the same. Hence the option (c).
17. If Young's double slit experiment is performed in water,
(a) the fringe width will decrease
(b) the fringe width will increase
(c) the fringe width will remain unchanged
(d) there will be no fringe
ANSWER: (a)
EXPLANATION: As the wavelength of light in water will decrease, hence the fringe width will decrease because the fringe width is proportional to the wavelength.
1. Light is
(a) wave phenomenon
(b) particle phenomenon
(c) both particle and wave phenomenon.
ANSWER: (c)
EXPLANATION: The photoelectric effect shows it as a particle phenomenon while the interference and diffraction of light shows it as a wave phenomenon. Hence duel nature.
2. The speed of light depends on
(a) on elasticity of the medium only
(b) on inertia of the medium only
(c) on elasticity as well as inertia
(d) neither on elasticity nor on inertia
ANSWER: (d)
EXPLANATION: The light does not require even a medium. The speed of light in a medium is the intrinsic property of that medium which is related to the refractive index of the medium.
3. The equation of a light wave is written as
y = A sin(kx-⍵t).
Here y represents
(a) displacement of ether particles
(b) pressure in the medium
(c) density of the medium
(d) electric field.
ANSWER: (d)
EXPLANATION: The light wave does not require a medium, hence the displacement of particles, the variation of pressure and density in the medium has no relation to the light wave. Light is an electromagnetic wave in which the electric field transverse to the motion of wave changes with time and place. Here y represents the electric field in the wave equation.
4. Which of the following properties show that light is a transverse wave?
(a) Reflection.
(b) Interference.
(c) Diffraction.
(d) Polarization.
ANSWER: (d)
EXPLANATION: The reflection, interference and diffraction effects are shown by both transverse and longitudinal waves. But polarization is only possible with a transverse wave because the transverse displacement of the particles of a medium or the transverse change of the electric field (as in lightwave) are in a plane and a slit perpendicular to this plane will not allow it to pass.
5. When light is refracted into a medium,
(a) its frequency and wavelength both increase
(b) its wavelength increases but frequency remains unchanged
(c) its wavelength decreases but frequency remains unchanged
(d) its wavelength and frequency both decrease.
ANSWER: (c)
EXPLANATION: When light is refracted into a medium its speed changes but the frequency remains the same because the energy associated with a photon of this light is proportional to the frequency of the light and it remains unchanged. Since the wavelength 𝜆 = c/𝜈, i.e. 𝜆 ∝ c. So the wavelength changes. Option (c) is true.
6. When light is refracted, which of the following does not change?
(a) wavelength.
(b) frequency.
(c) velocity.
(d) amplitude.
ANSWER: (b)
EXPLANATION: Same explanation as in question above.
7. The amplitude modulated (AM) radio wave bends appreciably round the corners of 1 m x 1 m board but frequency modulated (FM) wave only negligibly bends. If the average wavelengths of AM and FM waves are 𝜆ₐ and 𝜆ᵩ,
(a) 𝜆ₐ > 𝜆ᵩ
(b) 𝜆ₐ = 𝜆ᵩ
(c) 𝜆ₐ < 𝜆ᵩ
(d) we don't have sufficient information to decide about the relation of 𝜆ₐ and 𝜆ᵩ.
ANSWER: (a)
EXPLANATION: The wave having greater wavelength will bend more.
In fact, the frequency of the FM waves is nearly 100 times more than the AM waves hence the wavelength of the AM waves is 100 times more than FM waves.
8. Which of the following sources gives the best monochromatic light?
(a) A candle
(b) A bulb
(c) A mercury tube
(d) A laser.
ANSWER: (d)
EXPLANATION: The candle, bulb and mercury tube give lights of a mixture of wavelengths. In a laser, the same wavelength of light is processed and amplified. Hence the option (d).
9. The wavefronts of a light wave traveling in the vacuum are given by x+y+z = c. The angle made by the direction of propagation of light with X-axis is
(a) 0°
(b) 45°
(c) 90°
(d) cos⁻¹(1/√3).
ANSWER: (d)
EXPLANATION: The given equation of the wavefronts represent a plane that intersects each of the axes at a distance c from the origin. Let these points be named A, B and C. ABC is an equilateral triangle of side c.
The direction of propagation of light will be normal to the plane. In this case, the normal makes equal angles with each of the axes say α. Since the sum of the squares of the direction cosines equals one, here for the normal
cos²α+cos²α+cos²α = 1
→3 cos²α = 1
→cos²α = 1/3
→cos α = 1/√3
→α = cos⁻¹ (1/√3)
Hence the option (d).
10. The wavefronts of light coming from a distant source of unknown shape are nearly
(a) plane
(b) elliptical
(c) cylindrical
(d) spherical.
ANSWER: (a)
EXPLANATION: The wavefronts of light coming from a distant source are nearly plane because at a large distance the curve is magnified and a small portion of it is nearly plane.
11. The inverse square law of intensity (i.e. intensity ∝ 1/r²) is valid for a
(a) point source
(b) line source
(c) plane source
(d) cylindrical source.
ANSWER: (a)
EXPLANATION: Only for a point source the intensity can be written as I = E/4πr², where E is the strength of the source. Hence
E ∝ 1/r².
12. Two sources are called coherent if they produce waves
(a) of equal wavelength
(b) of equal velocity
(c) having same shape of wavefront
(d) having a constant phase difference.
ANSWER: (d)
EXPLANATION: By definition, the two sources are called coherent if the initial phase difference does not change with time i.e. the phase difference remains constant.
13. When a drop of oil is spread on a water surface, it displays beautiful colors in daylight because of
(a) dispersion of light
(b) reflection of light
(c) polarization of light
(d) interference of light
ANSWER: (d)
EXPLANATION: The drop of oil spreads on the water surface and makes a thin film. When the daylight is incident on the upper surface of the film, a part is reflected in the air while another is transmitted and falls on the inner surface. Here again, the light is reflected and transmitted in parts. The reflected light goes through this process multiple times and these multiple reflected rays have path differences and interfere with each other. If the following condition fulfilled for a certain wavelength, then this color is illuminated and display beautiful colors.
2µd = (n+½)𝜆
where d = thickness of the film and 𝜆 = wavelength of a certain color.
14. Two coherent sources of different intensities send waves which interfere. The ratio of maximum intensity to the minimum intensity is 25. The intensities of the sources are in the ratio
(a) 25:1
(b) 5:1
(c) 9:4
(d) 625:1
ANSWER: (c)
EXPLANATION: Since the resultant field at a point is given as
E₀² = E₁² + E₂² + 2E₁E₂ cos𝛿
Where E₁ and E₂ = amplitudes of interfering waves and 𝛿 is phase difference. For maximum amplitude cos𝛿 = 1 and for the minimum cos𝛿 = -1, hence maximum amplitude is given as
E₀² = (E₁ + E₂)²
and the minimum amplitude as
E₀'² = (E₁ - E₂)²
Since the intensity is proportional to the square of the amplitude, hence the maximum intensity
I = (√I₁ + √I₂)²
and the minimum intensity
I' = (√I₁ - √I₂)²
Let I₁ = k I₂
Hence, I = (√k+1)² I₂
and I' = (√k - 1)² I₂
Given, I/I' = 25
→(√k+1)²/(√k-1)² = 25
→√k + 1 = 5√k - 5
→4√k = 6
→√k =6/4 = 3/2
→k = 9/4
Hence the intensities of the sources are in the ratio 9:4.
15. The slits in a Young's double slit experiment have equal width and the source is placed symmetrically with respect to the slits. The intensity at the central fringe is I₀. If one of the slits is closed, the intensity at this point will be
(a) I₀
(b) I₀/4
(c) I₀/2
(d) 4I₀
ANSWER: (b)
EXPLANATION: As in the previous explanation the maximum intensity
I₀ = (√I₁ + √I₂)². Here given that I₁ = I₂ = I (say).
→I₀ = 4 I ------- (i)
If one slit is closed I₀' = I
→I₀' = I₀/4 {from (i)}
Hence option (b)
16. A thin transparent sheet is placed in front of a Young's double slit. The fringe width will
(a) increase
(b) decrease
(c) remain same
(d) become non-uniform
ANSWER: (c)
EXPLANATION: The fringe width is given as
w = D𝜆/d
where D = distance of the screen from the slits
d = distance of slits.
The wavelength 𝜆 remains the same when the light comes out of the film. Thus none of the entity D, d or 𝜆 changes. So the fringe with will remain the same. Hence the option (c).
17. If Young's double slit experiment is performed in water,
(a) the fringe width will decrease
(b) the fringe width will increase
(c) the fringe width will remain unchanged
(d) there will be no fringe
ANSWER: (a)
EXPLANATION: As the wavelength of light in water will decrease, hence the fringe width will decrease because the fringe width is proportional to the wavelength.
(a) wave phenomenon
(b) particle phenomenon
(c) both particle and wave phenomenon.
ANSWER: (c)
EXPLANATION: The photoelectric effect shows it as a particle phenomenon while the interference and diffraction of light shows it as a wave phenomenon. Hence duel nature.
2. The speed of light depends on
(a) on elasticity of the medium only
(b) on inertia of the medium only
(c) on elasticity as well as inertia
(d) neither on elasticity nor on inertia
ANSWER: (d)
EXPLANATION: The light does not require even a medium. The speed of light in a medium is the intrinsic property of that medium which is related to the refractive index of the medium.
3. The equation of a light wave is written as
y = A sin(kx-⍵t).
Here y represents
(a) displacement of ether particles
(b) pressure in the medium
(c) density of the medium
(d) electric field.
ANSWER: (d)
EXPLANATION: The light wave does not require a medium, hence the displacement of particles, the variation of pressure and density in the medium has no relation to the light wave. Light is an electromagnetic wave in which the electric field transverse to the motion of wave changes with time and place. Here y represents the electric field in the wave equation.
4. Which of the following properties show that light is a transverse wave?
(a) Reflection.
(b) Interference.
(c) Diffraction.
(d) Polarization.
ANSWER: (d)
EXPLANATION: The reflection, interference and diffraction effects are shown by both transverse and longitudinal waves. But polarization is only possible with a transverse wave because the transverse displacement of the particles of a medium or the transverse change of the electric field (as in lightwave) are in a plane and a slit perpendicular to this plane will not allow it to pass.
5. When light is refracted into a medium,
(a) its frequency and wavelength both increase
(b) its wavelength increases but frequency remains unchanged
(c) its wavelength decreases but frequency remains unchanged
(d) its wavelength and frequency both decrease.
ANSWER: (c)
EXPLANATION: When light is refracted into a medium its speed changes but the frequency remains the same because the energy associated with a photon of this light is proportional to the frequency of the light and it remains unchanged. Since the wavelength 𝜆 = c/𝜈, i.e. 𝜆 ∝ c. So the wavelength changes. Option (c) is true.
6. When light is refracted, which of the following does not change?
(a) wavelength.
(b) frequency.
(c) velocity.
(d) amplitude.
ANSWER: (b)
EXPLANATION: Same explanation as in question above.
7. The amplitude modulated (AM) radio wave bends appreciably round the corners of 1 m x 1 m board but frequency modulated (FM) wave only negligibly bends. If the average wavelengths of AM and FM waves are 𝜆ₐ and 𝜆ᵩ,
(a) 𝜆ₐ > 𝜆ᵩ
(b) 𝜆ₐ = 𝜆ᵩ
(c) 𝜆ₐ < 𝜆ᵩ
(d) we don't have sufficient information to decide about the relation of 𝜆ₐ and 𝜆ᵩ.
ANSWER: (a)
EXPLANATION: The wave having greater wavelength will bend more.
In fact, the frequency of the FM waves is nearly 100 times more than the AM waves hence the wavelength of the AM waves is 100 times more than FM waves.
8. Which of the following sources gives the best monochromatic light?
(a) A candle
(b) A bulb
(c) A mercury tube
(d) A laser.
ANSWER: (d)
EXPLANATION: The candle, bulb and mercury tube give lights of a mixture of wavelengths. In a laser, the same wavelength of light is processed and amplified. Hence the option (d).
9. The wavefronts of a light wave traveling in the vacuum are given by x+y+z = c. The angle made by the direction of propagation of light with X-axis is
(a) 0°
(b) 45°
(c) 90°
(d) cos⁻¹(1/√3).
ANSWER: (d)
EXPLANATION: The given equation of the wavefronts represent a plane that intersects each of the axes at a distance c from the origin. Let these points be named A, B and C. ABC is an equilateral triangle of side c.
 |
| Diagram for Q-9 |
The direction of propagation of light will be normal to the plane. In this case, the normal makes equal angles with each of the axes say α. Since the sum of the squares of the direction cosines equals one, here for the normal
cos²α+cos²α+cos²α = 1
→3 cos²α = 1
→cos²α = 1/3
→cos α = 1/√3
→α = cos⁻¹ (1/√3)
Hence the option (d).
10. The wavefronts of light coming from a distant source of unknown shape are nearly
(a) plane
(b) elliptical
(c) cylindrical
(d) spherical.
ANSWER: (a)
EXPLANATION: The wavefronts of light coming from a distant source are nearly plane because at a large distance the curve is magnified and a small portion of it is nearly plane.
11. The inverse square law of intensity (i.e. intensity ∝ 1/r²) is valid for a
(a) point source
(b) line source
(c) plane source
(d) cylindrical source.
ANSWER: (a)
EXPLANATION: Only for a point source the intensity can be written as I = E/4πr², where E is the strength of the source. Hence
E ∝ 1/r².
12. Two sources are called coherent if they produce waves
(a) of equal wavelength
(b) of equal velocity
(c) having same shape of wavefront
(d) having a constant phase difference.
ANSWER: (d)
EXPLANATION: By definition, the two sources are called coherent if the initial phase difference does not change with time i.e. the phase difference remains constant.
13. When a drop of oil is spread on a water surface, it displays beautiful colors in daylight because of
(a) dispersion of light
(b) reflection of light
(c) polarization of light
(d) interference of light
ANSWER: (d)
EXPLANATION: The drop of oil spreads on the water surface and makes a thin film. When the daylight is incident on the upper surface of the film, a part is reflected in the air while another is transmitted and falls on the inner surface. Here again, the light is reflected and transmitted in parts. The reflected light goes through this process multiple times and these multiple reflected rays have path differences and interfere with each other. If the following condition fulfilled for a certain wavelength, then this color is illuminated and display beautiful colors.
2µd = (n+½)𝜆
where d = thickness of the film and 𝜆 = wavelength of a certain color.
14. Two coherent sources of different intensities send waves which interfere. The ratio of maximum intensity to the minimum intensity is 25. The intensities of the sources are in the ratio
(a) 25:1
(b) 5:1
(c) 9:4
(d) 625:1
ANSWER: (c)
EXPLANATION: Since the resultant field at a point is given as
E₀² = E₁² + E₂² + 2E₁E₂ cos𝛿
Where E₁ and E₂ = amplitudes of interfering waves and 𝛿 is phase difference. For maximum amplitude cos𝛿 = 1 and for the minimum cos𝛿 = -1, hence maximum amplitude is given as
E₀² = (E₁ + E₂)²
and the minimum amplitude as
E₀'² = (E₁ - E₂)²
Since the intensity is proportional to the square of the amplitude, hence the maximum intensity
I = (√I₁ + √I₂)²
and the minimum intensity
I' = (√I₁ - √I₂)²
Let I₁ = k I₂
Hence, I = (√k+1)² I₂
and I' = (√k - 1)² I₂
Given, I/I' = 25
→(√k+1)²/(√k-1)² = 25
→√k + 1 = 5√k - 5
→4√k = 6
→√k =6/4 = 3/2
→k = 9/4
Hence the intensities of the sources are in the ratio 9:4.
15. The slits in a Young's double slit experiment have equal width and the source is placed symmetrically with respect to the slits. The intensity at the central fringe is I₀. If one of the slits is closed, the intensity at this point will be
(a) I₀
(b) I₀/4
(c) I₀/2
(d) 4I₀
ANSWER: (b)
EXPLANATION: As in the previous explanation the maximum intensity
I₀ = (√I₁ + √I₂)². Here given that I₁ = I₂ = I (say).
→I₀ = 4 I ------- (i)
If one slit is closed I₀' = I
→I₀' = I₀/4 {from (i)}
Hence option (b)
16. A thin transparent sheet is placed in front of a Young's double slit. The fringe width will
(a) increase
(b) decrease
(c) remain same
(d) become non-uniform
ANSWER: (c)
EXPLANATION: The fringe width is given as
w = D𝜆/d
where D = distance of the screen from the slits
d = distance of slits.
The wavelength 𝜆 remains the same when the light comes out of the film. Thus none of the entity D, d or 𝜆 changes. So the fringe with will remain the same. Hence the option (c).
17. If Young's double slit experiment is performed in water,
(a) the fringe width will decrease
(b) the fringe width will increase
(c) the fringe width will remain unchanged
(d) there will be no fringe
ANSWER: (a)
EXPLANATION: As the wavelength of light in water will decrease, hence the fringe width will decrease because the fringe width is proportional to the wavelength.
===<<<O>>>===
Links to the Chapters
===<<<O>>>===
Links to the Chapters
CHAPTER- 16 - Sound Waves
OBJECTIVE-I
OBJECTIVE-II
EXERCISES - Q-1 TO Q-10
EXERCISES - Q-11 TO Q-20
EXERCISES -Q-21 TO Q-30
EXERCISES -Q-31 TO Q-40
EXERCISES -Q-41 TO Q-50
EXERCISES -Q-51 TO Q-60
EXERCISES -Q-61 TO Q-70
EXERCISES - Q-71 TO Q-80
EXERCISES - Q-81 TO Q-89
CHAPTER- 15 - Wave Motion and Waves on a String
OBJECTIVE-II
EXERCISES - Q-1 TO Q-10
EXERCISES - Q-11 TO Q-20
EXERCISES - Q-21 TO Q-30
EXERCISES - Q-31 TO Q-40
EXERCISES - Q-41 TO Q-50
CHAPTER- 14 - Fluid Mechanics
CHAPTER- 13 - Fluid Mechanics
CHAPTER- 12 - Simple Harmonic Motion
EXERCISES- Q1 TO Q10
EXERCISES- Q11 TO Q20
EXERCISES- Q21 TO Q30
EXERCISES- Q31 TO Q40
EXERCISES- Q41 TO Q50
EXERCISES- Q51 TO Q58 (2-Extra Questions)
CHAPTER- 11 - Gravitation
EXERCISES -Q 31 TO 39
CHAPTER- 10 - Rotational Mechanics
CHAPTER- 9 - Center of Mass, Linear Momentum, Collision
CHAPTER- 16 - Sound Waves
OBJECTIVE-I
OBJECTIVE-II
EXERCISES - Q-1 TO Q-10
EXERCISES - Q-11 TO Q-20
EXERCISES -Q-21 TO Q-30
EXERCISES -Q-31 TO Q-40
EXERCISES -Q-41 TO Q-50
EXERCISES -Q-51 TO Q-60
EXERCISES -Q-61 TO Q-70
EXERCISES - Q-71 TO Q-80
EXERCISES - Q-81 TO Q-89
CHAPTER- 15 - Wave Motion and Waves on a String
EXERCISES - Q-1 TO Q-10
EXERCISES - Q-11 TO Q-20
EXERCISES - Q-21 TO Q-30
EXERCISES - Q-31 TO Q-40
EXERCISES - Q-41 TO Q-50
CHAPTER- 14 - Fluid Mechanics
CHAPTER- 13 - Fluid Mechanics
CHAPTER- 12 - Simple Harmonic Motion
EXERCISES- Q11 TO Q20
EXERCISES- Q21 TO Q30
EXERCISES- Q31 TO Q40
EXERCISES- Q41 TO Q50
EXERCISES- Q51 TO Q58 (2-Extra Questions)
CHAPTER- 11 - Gravitation
CHAPTER- 10 - Rotational Mechanics
CHAPTER- 9 - Center of Mass, Linear Momentum, Collision
CHAPTER- 8 - Work and Energy
Click here for → Question for Short Answers
Click here for → OBJECTIVE-I
Click here for → OBJECTIVE-II
Click here for → Exercises (1-10)
Click here for → Question for Short Answers
Click here for → OBJECTIVE-I
Click here for → OBJECTIVE-II
Click here for → Exercises (1-10)
Click here for → Exercises (11-20)
Click here for → Exercises (21-30)
Click here for → Exercises (31-42)
Click here for → Exercise(43-54)
Click here for → Exercises (21-30)
Click here for → Exercises (31-42)
Click here for → Exercise(43-54)
Click here for → Exercises (31-42)
Click here for → Exercise(43-54)
CHAPTER- 7 - Circular Motion
Click here for → Questions for Short Answer
Click here for → OBJECTIVE-I
Click here for → OBJECTIVE-II
Click here for → EXERCISES (1-10)
Click here for → EXERCISES (11-20)
Click here for → EXERCISES (21-30)
CHAPTER- 6 - Friction
Click here for → Questions for Short Answer
Click here for → OBJECTIVE-I
Click here for → OBJECTIVE-II
Click here for → EXERCISES (1-10)
Click here for → EXERCISES (11-20)
Click here for → EXERCISES (21-30)
Click here for → OBJECTIVE-I
Click here for → OBJECTIVE-II
Click here for → EXERCISES (1-10)
Click here for → EXERCISES (11-20)
Click here for → EXERCISES (21-30)
CHAPTER- 6 - Friction
Click here for → Questions for Short Answer
Click here for → Questions for Short Answer
Click here for → OBJECTIVE-I
Click here for → Friction - OBJECTIVE-II
Click here for → EXERCISES (1-10)
Click here for → Exercises (11-20)
Click here for → EXERCISES (21-31)
For more practice on problems on friction solve these- "New Questions on Friction".
Click here for → OBJECTIVE-I
Click here for → Friction - OBJECTIVE-II
Click here for → EXERCISES (1-10)
Click here for → Exercises (11-20)
Click here for → EXERCISES (21-31)
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CHAPTER- 5 - Newton's Laws of Motion
Click here for → QUESTIONS FOR SHORT ANSWER
Click here for → QUESTIONS FOR SHORT ANSWER
Click here for→ Newton's laws of motion - Objective - I
Click here for → Newton's Laws of Motion - Objective -II
Click here for → Newton's Laws of Motion-Exercises(Q. No. 1 to 12)
Click here for→ Newton's laws of motion - Objective - I
Click here for → Newton's Laws of Motion - Objective -II
Click here for → Newton's Laws of Motion-Exercises(Q. No. 1 to 12)
Click here for→Newton's Laws of Motion,Exercises(Q.No. 13 to 27)
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CHAPTER- 4 - The Forces
The Forces-
"Questions for short Answers"
Click here for "The Forces" - OBJECTIVE-I
Click here for "The Forces" - OBJECTIVE-II
Click here for "The Forces" - Exercises
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CHAPTER- 3 - Kinematics - Rest and Motion
Click here for "Questions for short Answers"
Click here for "OBJECTIVE-I"
Click here for EXERCISES (Question number 1 to 10)
Click here for EXERCISES (Question number 11 to 20)
Click here for EXERCISES (Question number 21 to 30)
Click here for EXERCISES (Question number 31 to 40)
Click here for EXERCISES (Question number 41 to 52)
CHAPTER- 2 - "Vector related Problems"
CHAPTER- 2 - "Vector related Problems"
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