Question

A diver estimates the depth of water in a swimming pool to be 10m,but realizes that it was much deeper when he dives into it. Explain why he was wrong in his judgement?

Answer 1

The diver was most likely wrong because of refraction. Light bends in water, leading to some optical illusions. In the case of the pool, the light bends as it enters the water, making it look shallower than what it really is when looked at from the top. Light rays reflected from the bottom of the pool are refracted at the surface of the water, however our eyes trace the light rays back into the water as though traveled in a straight line, and not refracted at all. This results in an image of the object that appears at a shallower depth to where it really is.