A fish is looking at a 1.0 m high plant at the edge of the pond. Will the plant appear shorter or taller than its actual height? Draw a ray diagram to support your answer.
A fish is looking at a 1.0 m high plant at the edge of the pond. Will the plant appear shorter or taller than its actual height? Draw a ray diagram to support your answer.

Solution:

The plant will appear to be taller than its real height.

Allow the fish to gaze from point O. Because air is a rarer material than water, when the ray OP comes from the water into air, it will bend away from the normal MN. However, if we extend the ray OP, it will intersect at Q. As a result, the plant AB will appear taller than it actually is.