Question

When a beam of white light is incident on a prism, the prism ______.

Options

• only disperses the incident light.

• only disperses the incident light.

• deviates as well as disperses incident light.

• neither deviates nor disperses incident light.

Answer 1

When a beam of white light is incident on a prism, the prism deviates as well as disperses incident light.

Explanation:

A prism bends (deviates) the light as it enters and exits, but because different colours of light have different wavelengths and speeds within the prism, they bend at slightly different angles, causing the white light to split into its constituent colours (dispersion).