Question

Suppose you are inside the water in a swimming pool near an edge. A friend is standing on the
edge. Do you find your friend taller or shorter than his usual height?

Answer 1

Answer on Question #40377, Physics, Optics

Suppose you are inside the water in a swimming pool near an edge. A friend is standing on the edge. Do you find your friend taller or shorter than his usual height?

Solution:

This diagram shows the person of height $d$ as seen from the pool (apparent height $d'$):

From below water, objects in air are virtual images that have an apparent position (height in air) greater than their real position.

The apparent height $d'$ can be found from the formula

$$d' = d \frac{n_2}{n_1}$$

where $d$ is the actual height and $n_2$ and $n_1$ are the refraction indices of the water and air, respectively.

**Answer.** The friend will seem taller than usual height.