Path of Light in Time-Varying Refractive Index: Straight or Curved?

[arpon]

Homework Statement

Suppose, light is passing through a liquid whose refractive index is time-varying. What will be the path of light ray ? Will it be a straaight line or curve ?

Homework Equations

The Attempt at a Solution

I think, it will be a straight line.

 

[Bystander]

time-varying

Are you certain the problem statement specified "time varying" and not a spatial variation such as refractive index of atmosphere with altitude?

 

[arpon]

Are you certain the problem statement specified "time varying" and not a spatial variation such as refractive index of atmosphere with altitude?

No spatial variation.

 

[haruspex]

I think, it will be a straight line.

I agree with your reasoning. By symmetry, there is no reason it should start curving one way rather than the other.