Question

A ray of light is incident through the centre of curvature of a spherical mirror , the reflected ray will
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Answer 1

More simple is that as ANGLE OF INCIDENCE = ANGLE OF REFLECTION

And as this incident ray falls on mirror at 90 degree (as it is at center of curvature)

THEREFORE

angle of REFLECTION = 90 degree and hence the ray will be reflected back along the same path.