4. What is the index of refraction? Does light travel faster in glass or in air and why? IF light traveled at the same speed in glass and in air, would glass lenses change the
direction of light? Explain your answer.

Arotating space station is said to create “artificial gravity”—a loosely-defined term used for an acceleration that would be crudely similar to gravity. the outer wall of the rotating space station would become a floor for the astronauts, and centripetal acceleration supplied by the floor would allow astronauts to exercise and maintain muscle and bone strength more naturally than in non-rotating space environments. if the space station is 200 m in diameter, what angular velocity would produce an “artificial gravity” of 9.80 m/s^{2} 2 at the rim?

The softest and hardest minerals are: softest hardest

What is a carrier wave and how does it affect what you hear on the radio