What should be the angle between two plane mirrorrs so that whatever be the angle of incidence, the incident ray and the reflected ray from the two mirrorrs be parallel to each other

Options

A. `60^(@)`
B. `90^(@)`
C. `120^(@)`
D. `45^(@)`

Answer

B

Explanation

(b) As incident ray and reflected ray are parallel to each other it means, deviation,
`delta=180^(@)`
`becausedelta=360^(@)-2theta`
Angle between two plane mirrors
`rArr theta=90^(@)`