A. incident angle is equal to the angle of refraction
B. refraction angle equals 90°
C. incident angle equals 90°
D. incident angle is equal to the angle of emergence
Correct Answer:
Option D – incident angle is equal to the angle of emergence
Explanation
At minimum deviation, it is observed that light passes symmetrically through, the prism such that the angle of incidence (i°) is angle to the angle of emergency (e°).(i/e I° = e°)

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