text: light refraction problems? this is about light waves.  1) what is the equation for finding the distance that light is laterally shifted after passing through a glass block given the index of refraction, the angle to the normal of the incident ray at the point that it enters the glass block, and the thickness of the block?  2) what is the equation for finding the time it takes for the light to pass through the same glass block? you'll never need to know this in your real life. join a band.