A ray of light is incident at an angle of `60^@` on the face of a prism having refracting angle `30^@.` The ray emerging out of the prism makes an angle `30^@` with the incident ray. Show that the emergent ray is perpendicular to the face through which it emerges.

Explanation

To solve the problem, we will use the principles of refraction at the interface of the prism and apply Snell's law. Let's go through the solution step by step.

### Step 1: Identify the given data
- Angle of incidence on the prism face, \( i_1 = 60^\circ \)
- Refracting angle of the prism, \( A = 30^\circ \)
- Angle between the emergent ray and the incident ray, \( \delta = 30^\circ \)

### Step 2: Use the relationship involving the angles
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