Physicshard · Past Paper

A ray of light is incident at 60 degrees on one face of an equilateral prism. If it suffers minimum deviation, the angle of refraction inside the prism is:

A60 degrees
B45 degrees
C30 degrees
D15 degrees

✓ Correct Answer: C30 degrees

For minimum deviation, r = A/2. In an equilateral prism, A = 60, so r = 30 degrees.

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