Question

A ray of light is incident on a 60° prism at the minimum deviation position. the angle of refraction at the first face (ie, incident face) of the prism is

Answer 1

Answer:

Angle of refraction at the first face (incident face) of the given prism is 30°

Explanation:

Given:

Angle of prism A = 60°

Solution:

For minimum deviation to occur, the condition is that the two angles of refraction of light are equal.

r1 = r2 = r

We know that the formula for the angle of prism is given by:

A= r1 + r2

So, A = r + r = 2r

r = 60° / 2 = 30°

Answer 2

Answer:30 degree

Explanation:for minimum deviation ina prism the refractive indexes r1 and r2 are same.The angle of prism is equal to sum of refractives indexes (we know that). There fore,

A=r1+r2

A=r+r=2r

A=2r. r=A/2. HereA=60

So r =30