Question

A beam of light is incident at an angle of 35 degrees with respect to the surface of a glass slab. After refraction, find the angle made by the emergent ray with respect to the surface of the glass slab.

• A. 35 degrees
• B. 23 degrees
• C. 59 degrees
• D. 42 degrees

Answer 1

The correct option is A 35 degrees

Given angle between the incident ray and the surface , $a={35}^{\circ }$.
Therefore, angle of incidence, $i={90}^{\circ }-{35}^{\circ }={55}^{\circ }$
We know, angle of incidence ($i$) = angle of emergence ($e$) $={55}^{\circ }$
The ray after emerging out of the glass slab makes an angle $b$ with the sutface of the glass slab.
$\therefore b={90}^{\circ }-{55}^{\circ }={35}^{\circ }$