Question

State the direction of incident ray which after reflection from a spherical mirror retraces its path. Give reason for your answer.

Answer 1

The incident ray which shows retracing of its path by a spherical mirror , will must be passing out through its centre of curvature.
The main reason that it don't deviates from its path is because it is considered perlendicular to the mirror hence,
angle of incident will be equal to angle of reflection which here both be zero. This no deviation from path.

Answer 2

It passes through centre of curvature