The speed of light in diamond is 125,000 km s^-1. What is the refractive index? (Speed of light in air = 3 x 10⁸ m s^-1).

The refractive index of water with respect to air is 4/3. What is the refractive index of air with respect to water?

In refraction of light through a prism, the light ray:

1. suffers refraction only at one face of the prism
2. emerges out from the prism in a direction parallel to the incident ray
3. bends at both the surfaces of the prism towards its base
4. bends at both the surfaces of prism opposite to its base.

In the figure given ahead the correct statement is:

1. ABED and ABC are the refracting surfaces.
2. line AD is the refracting edge
3. angle a is the angle of deviation
4. AB is the base of the prism.