Which statement is true?
A. Kepler’s laws apply only to the motion of Earth.
B. Kepler’s laws can be used to predict eclipses.
C. Kepler’s laws are true for a central force that is directly proportional to distance.
D. Kepler’s laws can be deduced from Newton’s laws of motion and gravity.

Awater slide of length l has a vertical drop of h. abby's mass is m. an average friction force of magnitude f opposes her motion. she starts down the slide at initial speed vi. use work-energy ideas to develop an expression for her speed at the bottom of the slide. then evaluate your result using unit analysis and limiting case analysis. express your answer in terms of the variables h, m, l, vi, f and appropriate constants. vf v f

Two point charges are separated by a certain distance. how does the strength of the electric field produced by the first charge, at the position of the second charge, change if the second charge is doubled? a. the field does not change b. the field strength decreases by half. c. the field strength doubles d. the field strength quadruples

The solid that is formed and usually sinks to the bottom of a solution is the