Refraction of Light through a Prism

Q.

Dispersion of light can be defined as the separation of white light beam into its seven constituent colors.

1. True
2. False

Q.

As light rays travel from air into a glass prism, they deviate away from the normal.

1. True

2. False

Q. Velocity of light in glass is $2\times {10}^{8}m{s}^{-1}$ and in air is $3\times {10}^{8}m{s}^{-1}$. If the ray passes through glass to air, calculate the value of critical angle.

1. ${40}^{\circ }$
2. ${42}^{\circ }$
3. ${45}^{\circ }$
4. ${50}^{\circ }$

Q. The line along which the two refracting faces meet is called the ___ of the prism.

1. Refracting edge
2. Refracting angle
3. Principal section
4. None of these

Q.

Light rays get refracted ______ when they pass from air to glass prism.

1. towards the normal

2. along the normal

3. along the air-glass interface

4. away from the normal

Q.

Question 27
Explain the refraction of light through a triangular glass prism using a labelled ray diagram. Hence define the angle of deviation.

Q.

State whether the following statement is 'true' or 'false' :

The deviation produced by a prism is independent of the angle of incidence and is the same for all colours of light.

Q.

What is a prism? With the help of a diagram of a principal section of a prism, indicate its refracting surfaces, refracting angle and base.

Q.

A light ray of yellow color is incident on an equilateral glass prism at an angle of incidence equal to 48${}^{\circ }$ and suffers minimum deviation by an angle of 36${}^{\circ }$. (i) What will be the angle of emergence? (ii) If the angle of incidence is changed to (a) 30${}^{\circ }$, (b) 60${}^{\circ }$, state in each case whether the angle of deviation will be equal to, less than or more than 36${}^{\circ }$?

Q. As light rays emerge from a glass prism into air, are they refracted towards or away from the normal ?