HARD
12th West Bengal Board
IMPORTANT
Earn 100

A small bulb is placed at the bottom of a tank containing water to a depth of 80 cm. What is the area of the surface of water through which light from the bulb can emerge out? The Refractive index of water is 1.33. Consider the bulb to be a point source of light.  

Important Questions on Refraction of Light

HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 13 - Refraction of Light>EXERCISE 13>Q 14
A small luminous source at the bottom of a pool of water(μ=4/3)1 metre deep, emits rays upward in all directions. A circular area of light is formed at the surface of water. Determine the radius of the circle. 
HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 13 - Refraction of Light>EXERCISE 13>Q 15
A ray of light falls on the plane horizontal face of a square glass slab at an angle of 45°. It is refracted into the block and is incident on one vertical face. What must be the refractive index of glass if total reflection occurs at the
HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 13 - Refraction of Light>EXERCISE 13>Q 16
Light enters a prism of refracting angle A at grazing incidence to emerge at an angle θ with normal. Show that the refractive index of the material of prism is :
μ=1+cosA+sinθsinA212   
HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 13 - Refraction of Light>EXERCISE 13>Q 17
The refracting angle of a prism is 30°. One of its refracting faces has a coating. A ray of light incident on the other face at an angle 45° falls on the coated surface. On reflection, the ray retraces its path. Find the refractive index of the material of the prism.
HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 13 - Refraction of Light>EXERCISE 13>Q 18
The angles of a prism immersed in water (μ=4/3) are 30°, 60° and 90°. A ray of light incident normally on a side adjacent to the right gets total internal reflection at the hypotenuse side and finally emerges from the other side. Within what range will the refractive index μ of the
material of the prism lie?
EASY
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 13 - Refraction of Light>EXERCISE 13>Q 19

A ray of light is incident normally at the face AB of a right-angled prism ABC [Fig] of μ=1.50. What is the largest value of the angle ∠ACB for which the ray is totally reflected at the surface AC?

Question Image

HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 13 - Refraction of Light>EXERCISE 13>Q 20
The refracting angle of a prism is 90°; If α is the angle of minimum deviation and β the angle of deviation of a ray which enters at grazing incidence, then show thatα=sin2β and cosα=μcosβ, where μ is the r . i of the prism.
HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 13 - Refraction of Light>EXERCISE 13>Q 21
The refractive of the material of a prism of refracting angle 45° is 1.6 for a certain monochromatic ray. What should be the minimum angle of incidence of this ray on the prism so that no total internal reflection takes place as the ray comes out of the prism?