Question

An object moves with velocity $10\text{m/s}$ towards the left while the mirror moves with velocity $2\text{m/s}$ towards the right as shown in the figure. The velocity of image with respect to ground will be

• A. $12\text{m/s}$ towards left
• B. $12\text{m/s}$ towards right
• C. $14\text{m/s}$ towards right
• D. $14\text{m/s}$ towards left

Answer 1

The correct option is C $14\text{m/s}$ towards right

Along perpendicular to the mirror,
Velocity of the object $w.r.t$ mirror $=-$ Velocity of the image $w.r.t$ to mirror
$\Rightarrow v_{om}=-v_{im}$
$\Rightarrow v_o-v_m=-(v_i-v_m)$
$\Rightarrow -10-2=-(v_i-2)$
$[$ taking rightward as $+$ $]$
$\Rightarrow v_i=14\text{m/s}$
Hence, the velocity of image with respect to ground will be $14\text{m/s}$ towards right.