Question

Keeping the incident ray fixed, if a plane mirror is rotated through an angle theta about an axis lying in its plane, then the reflected ray turns through an angle​

Answer 1

Given :

Angle of rotation of plane mirror = ∅

To Find :

The deflection angle of the reflected ray

Solution :

• Let, The angle of incidence = γ

• As the mirror is rotated through an angle ∅ the angle of incidence and angle of reflection also rotates by ∅

• Angle of incidence = γ + ∅

• For a plane mirror Angle of incidence is equal to Angle of reflection

• Angle of reflection =  ∅ + (γ + ∅)

                                 =2∅ + γ

The reflected ray turns through an angle of 2∅