Question

A ray of light is incident at an angle of `60^@` on the face of a prism having refracting angle `30^@.` The ray emerging out of the prism makes an angle `30^@` with the incident ray. Show that the emergent ray is perpendicular to the face through which it emerges and calculate the refractive index of the material of prism.

Answer 1

Correct Answer - C
`delta=i_1+i_2-A`
`30^@=60^@+i_2-30^@`
`:. i_2=0 or r_2=0`
Hence proved.
`rArr r_1=A=30^@`
Now, `mu=(sin i_1)/(sin r_2)=(sin 60^@)/(sin 30^@)=sqrt3`