Question

Assertion (A): When prism is in minimum deviation position, the angle of incidence is equal to angle of emergence.

Reason (R): For a prism ∠i + ∠e = ∠A + ∠δ.

Options

• Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion.

• Both Assertion (A) and Reason (R) are true but Reason (R) is not the correction explanation of Assertion.

• Assertion (A) is false, but Reason (R) is true.

• Assertion (A) is true, but Reason (R) is false.

Answer 1

Both Assertion (A) and Reason (R) are true but Reason (R) is not the correction explanation of Assertion.

Explanation:

Assertion (A) is true, at minimum deviation, the ray travels symmetrically through the prism, so the angle of incidence equals the angle of emergence. Reason (R) is also true and gives a general relation for a prism. However, that relation alone does not explain why the angles are equal at minimum deviation.