What happens to the energy of the electron when it absorbs a photon?
a. there is no change in the energy of the electron.
b. the energy of the electron increases.
c. the energy of the electron decreases.
d. the energy of the electron constantly varies.

Because light travels in a straight line and casts a shadow, isaac newton hypothesized that light is

Explain earth's motion, using the terms "precession" and "rotation" in your answer.

Cathy is pedaling down a steep hill on her bicycle and wants to be able to coast up the next hill, which is 25 meters high, without pedaling. cathy and her bicycle have a mass of 75 kg. assuming her bicycle is 100% efficient, what would her speed have to be?