Question

In
the
experiment of refraction through
glass slab, the
angle of incidence should be less than
90° .why?
​

Answer 1

The angle of incidence is nearly equal to the angle of emergence. The angle of refraction is less than angle of incidence because light is travelling from rarer to denser optical medium. The lateral displacement remains the same for different angles of incidences.

Answer 2

Explanation:

In the experiment of refraction through a glass slab the angle of incidence should be less than 90° because when the angle of incidence is equal to 90° the angle of refraction is also 90° incident ray will travel in the glass slab without changing direction.