# If a laser strikes a mirror with an angle of incidence of 36°, what is the angle between the angle of incidence and angle of reflection?

If you measure the angle of incidence from the normal, the angle of reflection will also be ${36}^{0}$ for a total of ${72}^{0}$
However if the ${36}^{0}$ you mention is the angle as measured from the plane of the mirror, then the angle of incidence (as measured from the normal) will be ${90}^{0} - {36}^{0} = {54}^{0}$ and the total angle will be twice that $2 \cdot {54}^{0} = {108}^{0}$.