Question
A point object $$'O'$$ is at the centre of curvature of a concave mirror. The mirror starts to move at a speed $$u,$$ in a direction perpendicular to the principal axis. Then, the initial velocity of the image is
A.
$$2u,$$ in the direction opposite to that of mirror's velocity
B.
$$2u,$$ in the direction same as that of mirror's velocity
C.
zero
D.
$$u,$$ in the direction same as that of mirror's velocity
Answer :
$$2u,$$ in the direction same as that of mirror's velocity
Solution :
Image velocity (w.r.t mirror) $$ = - m \times {\text{object}}\,{\text{velocity}}\left( {{\text{w}}{\text{.r}}{\text{.t}}\,{\text{mirror}}} \right)$$
Here $$m = 1$$