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 parallel mirrors $M_1$ and $M_2$ are separated by a distance $a$. An object is placed between them. What is the distance between the $n^{th}$ image formed by $M_1$ and the $n^{th}$ image formed by $M_2$?

$A$ plane mirror makes an angle of $30^\circ$ with the horizontal. If a vertical ray strikes the mirror,find the angle between the mirror and the reflected ray.

$A$ ray of light making an angle $10^o$ with the horizontal is incident on a plane mirror making an angle $\theta$ with the horizontal. What should be the value of $\theta$ so that the reflected ray goes vertically upwards?

Two plane mirrors are inclined to each other such that a ray of light incident to the first mirror $(M_1)$ and parallel to the second mirror $(M_2)$ is finally reflected from the second mirror $(M_2)$ parallel to the first mirror $(M_1).$ The angle between the two mirrors will be......$^o$

An object is fixed at the bottom of a vessel and water is filled in the vessel up to a height of $10 \,cm$. $A$ plane mirror is placed at a height of $7 \,cm$ from the surface of water in such a way that its reflecting surface faces the water. The distance of the image from the mirror is (Refractive index of water,$n=1.33$). (in $\,cm$)