NEET Physics Refraction of Light at Plane Surface and Total Internal Reflection MCQs Set A

a) its wavelength increases but frequency remains unchanged

b) its wavelength decreases but frequency remains unchanged

c) its wavelength and frequency both decrease

d) its wavelength and frequency both increase

Answer: its wavelength increases but frequency remains unchanged

Question: Total internal reflection can take place only if

a) light goes from optically denser medium to rarer medium

b) the refractive indices of the two media are close to different

c) the refractive indices of the two media are widely different

d) light goes from optically rarer medium (smaller refractive index) to optically denser medium

Answer: light goes from optically denser medium to rarer medium

Question: When the angle of incidence of a light ray is greater than the critical angle it gets

a) total internally reflected

b) critically refracted

c) totally reflected

d) totally refracted

Answer: total internally reflected

Question: Critical angle of light passing from glass to water is minimum for

a) violet colour

b) green colour

c) red colour

d) yellow colour

Answer: violet colour

Question:  Light travels through a glass plate of thickness t and refractive index m. If c is the speed of light in vacuum, the time taken by light to travel this thickness of glass is

a)

b)

c)

d)

Answer:

Question:  One face of a rectangular glass plate 6 cm thick is silvered. An object held 8 cm in front of the first face, forms an image 12 cm behind the silvered face. The refractive index of the glass is

a) 1.2

b) 1.6

c) 0.8

d) 0.4

Answer: 1.2

Question: Light travels in two media A and B with speeds 1.8 × 10⁸ m s^–1 and 2.4 × 10⁸ m s^–1 respectively. Then the critical angle between them is

a)

b)

c)

d) None of these

Answer:

 More Questions.....................................

Question:

a) The spectrum of visible light whose frequency is less than that of green light will come out to the air medium

b) The spectrum of visible light whose frequency is more than that of green light will come out to the air medium

c) The entire spectrum of visible light will come out of the water at various angles to the normal

d) The entire spectrum of visible light will come out of the water at an angle of 90º to the normal

Answer: The spectrum of visible light whose frequency is less than that of green light will come out to the air medium

Question:  A glass slab of thickness 4 cm contains the same number of waves as 5 cm of water when both are traversed by the same monochromatic light. If the refractive index of water is 4/3, what is that of glass?

a) 5/3

b) 5/4

c) 16/15

d) 1.5

Answer: 5/3

Question: A ray of light is travelling from glass to air. (Refractive index of glass = 1.5). The angle of incidence is 50°. The deviation of the ray is

a) 80°

b)

c) 0°

d)

Answer:  80°

Question:

a)

b)

c)

d) None of these

Answer:

Question:  When light passes from denser to rarer medium, then which of the following combination is correct ?

a)

b)

c)

d)

Answer:

Question:

a)

b)

c)

d)

Answer:

Question:

a) emerge into the air with an angle of refraction equal to 90º

b) be absorbed

c) be reflected back into the glass

d) emerge into the air without any deviation

Answer:  emerge into the air with an angle of refraction equal to 90º

Question:

a)

b)

c)

d)

Answer: