For a given incident ray if the plane mirror is rotated by an angle `20^@`, what angle does the reflected light gets rotated?

If incident ray strikes the mirror at 90^@ , what will be the angle of reflection?

What is the angle of incidence of a ray if the reflected ray is at an angle of 90^@ to the incident ray?

What is the angle of incidence of a ray if the reflected ray is at an angle of 90^@ to the incident ray ?

Two plane mirrors l and m are placed perpendicular to each other as shown in the figure. An incident ray AB to the first mirror is reflected in the directin of BC and then reflected by the second mirror in the direction CD. Prove that AB||CD

A ray of light is incident on a medium at polarising angle .What is the angle betweeen the relfected and refracted rays?