Question

A student traces the path of a ray of light through a glass prism for different angles of incidence. He analyses each diagram and draws the following conclusion:

1. On entering the prism, the light ray bends towards its base.
2. Light ray suffers refraction at the point of incidence and at the point of emergence while passing through the prism.
3. An emergent ray bends at a certain angle to the direction of the incident ray.
4. While emerging from the prism at the second surface, the angle of refraction is less than the angle of incidence at that surface.

Options

• I, II and III

• I, III and IV

• II, III and IV

• All of these.

Answer 1

I, II and III

Explanation:

Statements I, II and III are correct. A prism deviates light towards its base and the ray refracts at both surfaces, emerging in a direction different from the incident ray.

Statement IV is false because, when light emerges from glass into air, it bends away from the normal, so the angle of refraction is greater than the angle of incidence.