Optics Ques 117
- The graph between angle of deviation ( $\delta$ ) and angle of incidence $(i)$ for a triangular prism is represented by
(2013 Main)
(a)

(b)

(c)

(d)

Show Answer
Answer:
Correct Answer: 117.(c)
Solution:
Formula:
- We know that the angle of deviation depends upon the angle of incidence. If we determine experimentally, the angles of deviation corresponding to different angles of incidence and then plot $i$ (on- $X$-axis) and $\delta$ (on- $Y$-axis), we get a curve as shown in figure.

Clearly if angle of incidence is gradually increased, from a small value, the angle of deviation first decreases, becomes minimum for a particular angle of incidence and then begins to increase.