Assertion: If angle of incidence in case of a prism is gradually increased, then deviation produced by prism will first decrease, then increase.
Reason: At minimum deviation, `r_(1) =A/2`.

Options

A. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B. If both Assertion and Reason are true but Reason is not correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If Assertion is false but Reason is true.

Answer

B

Explanation

(b) For minimum deviation,

and
`because A=r_(1)+r_(2)`
`therefore r_(1)=r_(2)=A/2`