What happens to the speed of light as light from the sun enters the earth's atmosphere and shines down into the oceans, and why?
a. the light speeds up as it enters the atmosphere, and slows as it enters the water because water is a denser medium than air so it absorbs more of the light's energy.
b. the light slows down as it enters the atmosphere because the air absorbs some light energy; the light speeds up in the water because light moves faster through liquids.
c. the light speeds up as it enters the atmosphere and then speeds again as it enters the water because light is able to absorb energy from each medium through which it travels.
d. the light slows down as it enters the atmosphere, and then slows again as it enters the water because some of its energy is absorbed by the different media through which it passes.