At what angle (in degrees) should two plane mirrors be inclined to obtain $3$ images?

$A$ small plane mirror is placed at the center of a spherical screen of radius $R$. Light rays are incident on the mirror. If the mirror is rotated at a frequency of $n$ revolutions per second,what will be the speed of the reflected light spot on the screen?

Two plane mirrors $A$ and $B$ are placed parallel to each other as shown in the figure. $A$ light ray is incident on mirror $A$ at an angle of $30^o$. The plane of incidence coincides with the plane of the figure. What is the maximum number of reflections (including the first one) the ray will undergo before emerging?

An object is at a distance of $0.5 \ m$ in front of a plane mirror. The distance between the object and its image is ..... $m$.

$A$ light ray makes an angle of $10^o$ with the horizontal. It strikes a plane mirror inclined at an angle $\theta$ to the horizontal,and the reflected ray becomes vertical. What is the value of the angle $\theta$ in degrees?

$A$ two-eyed man is looking at the junction of two mutually perpendicular mirrors from a far-off distance. Assume no reflection occurs from the edge. If both eyes are open,then: