Consider the situation shown in Figure. A plane mirror is fixed at a height h above the bottom of a beaker containing water (refractive index `mu`) upto a height d. Find the position of the image of bottom formed by the mirror.

Explanation

The bottom of the beaker appears to be shifted up by a distance
`Deltat=(1-(1)/(mu))d`
Thus, the apparent distance of the bottom from the mirror is `h-Deltat=h-[1-(1//mu)]^(d)=h-d+(d//mu).` The image is formed behind the mirror at a distance `h-d+(d//mu).`