Question

why does the beam of light change direction when it enters the water

Answer 1

The bending occurs because light travels more slowly in a denser medium. ... As the light enters the water, it is refracted. Since the light is passing from air (less dense) into water (more dense), it is bent towards the normal. The beam of light would appear to bend at the surface of the water.

Answer 2

The bending occurs because light travels more slowly in a denser medium. ... As the light enters the water, it is refracted. Since the light is passing from air (less dense) into water (more dense), it is bent towards the normal. The beam of light would appear to bend at the surface of the water.

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