Question

what is the effect of medium density on the speed of light waves?
speed increases with higher density
no effect
speed fluctuates unpredictably
speed decreases with higher density

Explanation:

Light waves travel slower in denser media. This is because in a denser medium, there are more particles for the light waves to interact with. These interactions cause the light waves to be absorbed and re - emitted, which takes time and effectively slows down the overall speed of the light wave. For example, light travels slower in water (a denser medium compared to air) than in air.

Answer:

Speed decreases with higher density