Question

an incident ray makes an angle of 75 degree with the surface of the plane mirror what will be the angle of reflection

Answer 1

the angle made with the surface is 75 degrees so the angle of incidence is (90-75)=15 degrees so angle of reflection=angle of incidence=15 degrees

Answer 2

The angle made by the normal will be 90 – 75 = 15. Angle made by normal is equal to angle of incidence. So i = 15 degree. And by the law of reflection which states that angle of incidence is equal to the angle of reflection, the angle of reflection will be 15 degree