Question

Explain why a swimming pool full of water appears less deep than it actually is.

Answer 1

A swimming pool full of water appears to be less deep than it actually is. This is because an optically denser medium (i.e., water) when seen from an optically rarer medium (i.e., air), appears less deep than it actually is. When a ray of light passes from air to water it bends towards the normal, but when the ray passes from water to air, it bends away from the normal. Thus, emergent rays come from virtual image which is above the bottom of pool and therefore, it appears to be less deep.