A ray of light is incident on a glass sphere of refractive index 3/2. What should be the angle of incidence so that the ray which enters the sphere does not come out of the sphere ?

Options

A. `tan^(-1)(2//3)`
B. `60^(@)`
C. `90^(@)`
D. `30^(@)`

Answer

c.

Explanation

`angleABO=angleOAB=theta_(c)`
`sintheta_(C)=(1)/(mu)=(2)/(3)`
Applyinig Snell's law at A
`(sini)/(sintheta_(C))=(3)/(2)`
`sini=((3)/(2))((2)/(3))=1`
or `i=90^(@)`