Question

If an observer is walking away from the plane mirror with 6m/sec. Then the velocity of the image with respect to observer will be

Answer 1

As per the question the velocity of observer with respect to mirror is 6 m/s.

We are asked to calculate the velocity of image with respect to the observer.

         $Let\ V_{IM}=Velocity\ of\ image\ with\ respect\ to\ mirror$

                $V_{IO} =Velocity\ of\ image\ with \ respect\ to\ object$

                $V_{MO} =Velocity\ of\ mirror\ with\ respect\ to\ object$

                $Again\ V_{MO} =\ -V_{OM}$

We know that velocity of image with respect to mirror is same in magnitude with velocity of object with respect to mirror,but opposite in direction.

We know that-

                       $V_{IO} =V_{IM} +V_{MO}$

                       $V_{IO} =V_{IM} -V_{OM}$

                                         = -6 m/s -6 m/s

                                         = -12 m/s

The negative sign is due to the fact that image velocity is just opposite to the object velocity.

Answer 2

the velocity of image with respect to observer will be -12m/s