Question

A ray of light falls on one face of an equilateral glass prism at 40∘ and emerges from the other face at the same angle. The deviation suffered by the ray is ....?​

Answer 1

Answer:

Given: A light ray falls on one of the faces of a prism at an angle 40o so that it suffers angle of minimum deviation of 30o.

To find the angle of prism and angle of refraction at the given surface

Solution:

According to the given criteria,

Angle of incidene, i=40∘

Angle of minimum deviation, δm=30∘

We know

δm=2i−A, where A is refracting angle of theprism

⟹A=2i−δm⟹A=2(40)−30⟹A=50∘

is the required angleof the prism.

And we also know in case of minimum deviation

A=2r, where r is refraction angle

So, r=2A=250⟹r=25∘

is the required angle of refraction

Answer 2

Answer:

20 degree

Explanation:

here angle a is 60 degree

so angle i + angle e -angle a = ur answer

40+40-60+20 degree