It is desired to photograph the image of an object placed at a distance of $3\;m$ from a plane mirror. The camera,which is at a distance of $4.5\;m$ from the mirror,should be focused for a distance of......$m$.

$A$ man runs towards a plane mirror at a speed of $15 \ m/s$. What is the speed of his image relative to the mirror? (in $m/s$)

Two plane mirrors are placed parallel to each other at a distance $L$ apart. $A$ point object $O$ is placed between them,at a distance $L/3$ from one mirror. Both mirrors form multiple images. The distance between any two images cannot be:

Two plane mirrors are at $45^{\circ}$ to each other. If an object is placed between them,then the number of images will be

$A$ ray of light travelling in the direction $\frac{1}{2}(\hat{i}+\sqrt{3} \hat{j})$ is incident on a plane mirror. After reflection,it travels along the direction $\frac{1}{2}(\hat{i}-\sqrt{3} \hat{j})$. The angle of incidence is: (in $^{\circ}$)

The coordinates of the image with respect to the origin $c$ will be