Answer
See answers.
Work Step by Step
See the sketch. The solid lines are the paths followed by lights rays from the actual position of the stars. The dot is the person standing on Earth, looking at stars through the atmosphere.
a. The light rays bend toward the vertical direction as they enter Earth’s atmosphere, and this makes sense. Air’s index of refraction is slightly greater than 1, the index of vacuum. As the light rays enter the atmosphere, they slow down and bend toward the normal (which is the vertical direction), in agreement with Snell’s law.
b. The dotted lines represent the direction from which the light rays appear to come, according to the observer on Earth. We note that the apparent positions of the stars are too high above the horizon, compared to the actual positions.
