WAEC - Physics (1992 - No. 21)
A ray of light strikes a plane mirror at an angle of incidence i. Determine in terms of i the angle of deviation of the ray after reflection from the mirror.
i
2i
90o-i
90o+ i
180o - 2i
ব্যাখ্যা
the angle of deviation = 180 - the angle of incidence - the angle of reflection
but angle of incidence = angle of reflection(snell's law)
then angle of deviation = 180 - 2i