A parallel beam of light falls normally on the first face of a prism of small angle .At the second face it is partly reflected,the reflected beam striking at the first face again, and emerging from it in a direction making an angle `6^(@)` 30' with the reversed direction of the incident beam. The refracted beam is found to have undergone a deviation of `1^@ 15'` from the original direction.Find the refractive index of the glass and the angle of the prism.

Answer

A, B

Explanation

As the angles are small we can take,

`sin theta~~theta`
Now, `mu=(A+1^@15')/A`
`=(6^@30')/2A`
Solving this equation, we get
`A=2^@`
and `mu=1.62`