Describe how a light wave changes as it travels from the air into water.

Question

a
It speeds up because water is less dense than air.
b
It speeds up because water is more dense than air.
c
It slows down because water is less dense than air.
d
It slows down because water is more dense than air.

Answer 1

d. It slows down because water is more dense than air.

As the light wave travels from air into water, it enters into a medium that is more optically dense than air. This causes the light wave to slow down as it enters the water. Additionally, the change in density causes the light wave to refract or bend as it enters the water.