The distance between two objects is increased by 3 times the original distance. how will this change the force of attraction between the two objects?
a. the new force will be 1/3 of the original.
b. the new force will be 3 times more than the original.
c. the new force will be 1/9 of the original.
d. the new force will be 9 times more than the original.

a lot of it means it can be "burned" for energy and sold at one price. if it is scarce, the price will go up

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.