Answer: The angle of deviation in a plane mirror is calculated as δ=(180
o
−2i)
In this case, the angle of deviation is given as 60
o
.
Substituting in the above equation we get, 60
o
=(180
o
−2i).
So, i=60
o
According to the law of reflection, the angle of incidence equals the angle of reflection.
Therefore, angle of incidence i = angle of reflection r = 60
o
