If a light ray is reflected from a mirror as shown in the figure, then

Options

A. the glancing angle of light ray is `45^@`
B. the reflected light ray is perpendicular to the incident light ray.
C. the reflected light is deviated through an angle of `90^@`
D. All of the above

Answer

D

Explanation

(1) From the figure

`i + r = 90^@`
But i =r
`2i = 90^@`
`i = 45^@`
`angle x + angle i = 90^@`
`angle x = 90^@ - 45^@`
` = 45^@`
(2) From the given figure `angle POQ = 90^@` , i.e., reflected light is perpendicular to incident light.
(3) From figure ,` gamma = 90^@ - 45^@ = 45^@ ` and `angle POM = angle NOQ`
` therefore angle QOQ^1 = ` angle of deviation
` = angle QON + angle NOQ^1`
` = 45^@ + 45^@`
` = 90^@`