Question

An object and a plane mirror are shown in figure. Mirror is moved with velocity V as shown. The velocity of image is :

• A. $2Vsin\theta$
• B. $2V$
• C. $2Vcos\theta$
• D. none of these

Answer 1

The correct option is B $2V$

By using relative velocity concept velocity of image w.r.t mirror $r=V$,

velocity of image w.r.t ground $=O$

velocity of mirror w.r.t ground $=V$

velocity of image w.r.t mirror $=$ absolute velocity of image $-$ absolute velocity of mirror

$V=$ absolute velocity of image $=V$

absolute velocity of image $=2V$

velocity at image w.r.t mirror $=$ absolute velocity of image $-$ absolute velocity mirror $=2V-0=2V$