The distance of an object from a spherical mirror is equal to the focal length of the mirror. Then the image :

A concave mirror of focal length $20\mathrm{cm}$ is cut into two parts from the middle and the two parts are moved perpendicularly by a distance $1\mathrm{mm}$ from the previous principal axis $\mathrm{AB}$. The distance between the images formed by the two parts is:

Radius of curvature of each mirror is $\mathrm{R}$. $\mathrm{O}$ is object. Consider first reflection from concave mirror. Consider only first three reflection. The distance of final image from convex mirror is 

Consider the situation shown in figure. Water $\left({\mu }_W=\frac{4}{3}\right)$ is filled a beaker upto a height of $10 \mathrm{cm}$. A plane mirror is fixed at a height of $5 \mathrm{cm}$ from the surface of water. Distance of image from the mirror after reflection from it of an object $\mathrm{O}$ at the bottom of the beaker is-

A plane mirror is placed at the bottom of a tank containing a liquid of refractive index $\mu$. $P$ is a small object at a height $h$ above the mirror. An observer $O$ Vertically above $P$,outside the liquid sees $P$ and its image in the mirror. The apparent distance between these two will be:

When a pin is moved along the principal axis of a small concave mirror, the image position coincides with the object at a point $0.5 \mathrm{m}$ from the mirror, refer to figure. If the mirror is placed at depth of $0.2 \mathrm{m}$ in a transparent liquid, the same phenomenon occurs when the pin is placed $0.4 \mathrm{m}$ form the mirror. The refractive index of the liquid is: