Question

A point object is moving with speed $v$ in front of the arrangement of two perpendicular plane mirrors as shown in the figure. The magnitude of velocity of image in mirror $M_1$ with respect to image in mirror $M_2$ will be

• A. $2v$
• B. $3v$
• C. $0$
• D. $v/2$

Answer 1

The correct option is A $2v$

The velocity of the image formed in respective mirrors is shown in the diagram.

Therefore, the velocity of the image in mirror $M_1$ $w.r.t$ image in mirror $M_2$ will be,
$\Rightarrow v_{12}=v_1-v_2$
$\Rightarrow v_{12}=-v-(+v)=-2v$
$[$ taking rightward as $+$ $]$
$\therefore |v_{12}|=2v$