Question

angle of prism is 60 degree and angle of incidence is 35°and angle of emergence is 45 then find angle of deviation

Answer 1

Least angle of deviation (or angle of minimum deviation) is 36 degrees.

Angle i denotes angle of incidence.

Angle e denotes angle of emergence.

i + e = Angle of prism + Angle of deviation

Here, in case of minimum deviation, where the prism angle is 60 degrees, i and e would be equal to each other.

So, 2i = A + Angle of deviation

2 (48) = 60 + Angle of deviation

96 - 60 = Angle of deviation

36 degrees is equal to the angle of deviation.