What happens to speed of light from water to air?

Answer 1

It speeds up.

Air and water are both media (plural form of medium). Each one of them has a different speed of light. As the incident ray passes from air to water, it refracts to be closer to the normal. A refraction occurs when there is a change in the speed of light. A change in the speed of light occurs when there is a change in media. In this case the media is changed from air to water. The second medium (water) must also have a lower speed of light in order for refraction to occur

Answer 2

The index of refraction of air is considerably less than the index of refraction

for water. This is an indication that when light transitions the boundary out

of water and into air, its speed increases..

Answer 3

The speed of light itself actually increases, based on what recent studies say. If this question truly does mean from water to air, and not the other way around, then this is true. While the speed (very slightly) increases, the ray of light will attempt to "straighten itself out" to face upwards, an initial position for light passing from water to air, or vise-versa.

Answer 4

How does the speed of light change as it moves from space to air to water?