Two mirrors $AB$ and $CD$ are arranged along two parallel lines. The maximum number of images of object $O$ that can be seen by any observer is

In the figure shown,how many images of the star will an observer at $O$ see?

$A$ ray of light is incident at $50^{\circ}$ on the middle of one of the two mirrors arranged at an angle of $60^{\circ}$ between them. The ray then touches the second mirror,gets reflected back to the first mirror,making an angle of incidence of.........$^{\circ}$

$A$ plane mirror makes an angle of $30^\circ$ with the horizontal. $A$ vertical ray is incident on the mirror. What is the angle between the mirror and the reflected ray in degrees?

Two plane mirrors are kept on a horizontal table making an angle $\theta$ with each other as shown schematically in the figure. The angle $\theta$ is such that any ray of light reflected after striking both the mirrors returns parallel to its incident path. For this to happen,the value of $\theta$ should be (in $^{\circ}$)

$A$ man runs towards a plane mirror at a speed of $15 \, m/s$. The speed of the image relative to the mirror is ...... $m/s$.