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:

S.No.	$\angle i$	$\angle r$	$\angle e$
I	${30}^o$	${20}^o$	${31}^o$
II	${40}^o$	${25}^o$	${40}^o$
III	${50}^o$	${31}^o$	${49}^o$

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

Condition 1-

Angle of Incidence $\angle i\approx$ Angle of Emergent $\angle e$ (Experimental values)

and Angle of Refraction $\angle r<$ Angle of Incidence $\angle i$.

Condition 2-

When Angle of Incidence $\angle i$ increase corresponding Angle of Refraction $\angle r$ should also increase.

In above Table, all the 3 observations are valid for the conditions.