Question

After tracing the path of rays of light through a glass slab for three different angles of incidence, a student measured the corresponding values angle of refraction r and angle of emergence e and recorded them in the table given below
$\begin{array}{cccc}S.NO& \angle i& \angle i& \angle e\\ I& {30}^{\circ }& {20}^{\circ }& {31}^{\circ }\\ II& {40}^{\circ }& {25}^{\circ }& {40}^{\circ }\\ III& {50}^{\circ }& {31}^{\circ }& {49}^{\circ }\end{array}$
The correct observations are

• A. I and II
• B. II and III
• C. I and III
• D. I, II and III

Answer 1

The correct option is D

I, II and III

For light rays passing through a glass slab, the following conditions should hold true:

$\left(1\right)\angle i\approx \angle eand\angle r<\angle i$

(2) Also, with the increase in incident angle, the refracted angle also increases.

Both of these conditions are satisfied in all the three observations.