Question

When red light is refracted by a glass prism such that the angle of deviation is minimum, the angle of emergence is ______ the angle of incidence.

Options

• greater than

• less than

• equal to

• none of these

Answer 1

When red light is refracted by a glass prism such that the angle of deviation is minimum, the angle of emergence is equal to the angle of incidence.

Explanation:

Under the condition of minimum deviation (δ_m) in a prism, the ray of light passes symmetrically through the prism. Because of this perfect symmetry, the angle of incidence (i) is always exactly equal to the angle of emergence (e).