Question

Two identical prisms 1 and 2, each will angles of 30⁰, 60⁰ and 90⁰ are placed in contact as shown in figure. A ray of light passed through the combination in the position of minimum deviation and suffers a deviation of 30⁰. If the prism 2 is removed, then the angle of deviation of the same ray is

• A. Equal to 15⁰
• B. Smaller than 30⁰
• C. More than 15⁰
• D. Equal to 30⁰

Answer 1

Answer: (A)

Equal to 15⁰

Answer 2

$\delta = ( \mu - 1 ) A$ as A is halved, so $\delta$is also halves