A ray of light strikes a plane mirror at an angle of 40° to the mirror surface. What will be the angle of reflection?

Therefore, the angle of incidence (the angle between the incident ray and the normal) = 90°$-$ 40°= 50°

Now, we know that according to the law of reflection, the angle of incidence is equal to the angle of reflection.

Therefore, the angle of reflection will be 50°.

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