Refraction and spearing a fish

We now know that a light ray travelling from air to water will be refracted (change direction) and so too will light from water to air.

$Refracted light ray travelling from water to air.$

This means that if you are trying to spear a fish in the water . . .

Man trying to spear a fish where it appears to be in the water.

. . . you must make adjustment.

$Actual position of the fish as a result of refraction.$

Adjust the angle of throw.

New direction the spear should be thrown to catch the fish.

This effect becomes yet more acute when the angle of the light ray is even shallower.

$Refraction effect on the fish's position becomes greater with a shallower angle.$

Notice too that the fish appears to be at a shallow depth but it is a lot deeper in actuality.

$Refraction also affects the appearance of the fish's depth in the water.$

The refraction of light at the surface of water makes ponds and swimming pools appear to be a lot shallower than they really are.