Question

A ray of light is incident at an angle of incidence \( i \) on one surface of a thin prism of small angle \( A \). The ray emerges normally from the opposite surface. If the refractive index of the material of the prism is \( \mu \), the angle of incidence \( i \) is nearly equal to

• A. \( \frac{A}{\mu} \)
• B. \( \frac{\mu A}{2} \)
• C. \( \mu A \)
• D. \( \frac{A}{2 \mu} \)

Hint:

For small angle prisms, the angle of incidence is approximately equal to the product of the refractive index and the prism angle.

Answer 1

The Correct Option is C

Step 1: Understanding the problem.
In a thin prism, when the ray emerges normally from the opposite surface, the angle of incidence \( i \) is related to the angle of the prism \( A \) and the refractive index \( \mu \). The relationship is given by the formula: \[ i = \mu A \] Step 2: Conclusion.
Thus, the correct answer is (C) \( \mu A \).