1.

a. What is the speed of light in air?

b. What is the speed of light in crown glass?

2.

a. Calculate the index of refraction for a medium in which the speed of light is 1.99510⁸ m/s, and identify the most likely substance based on Table 25.1. Note: There is some uncertainty in the speed of the light in the medium.

b. The substance is most likely what?

3. Components of some computers communicate with each other through optical fibers having an index of refraction n = 1.49. What time in nanoseconds is required for a signal to travel 0.180 m through such a fiber? (You do not need to enter any units.)

4. A scuba diver training in a pool looks at his instructor as shown in the figure below. What angle does the ray from the instructor's face make with the perpendicular to the water at the point where the ray enters? The angle between the ray in the water and the perpendicular to the water is 25.0.

1.2 m d=1.8 m