As the distance between two masses increases, the gravitational force of attraction between them

a. decreases
b. increases
c. remains the same

Which is not a characteristic of a heat pump? a. it is used in air conditioners. b. it uses a refrigerant. c. it requires no work. d. it reverses the normal flow of thermal energy.

If a refrigerator is a heat pump that follows the first law of thermodynamics, how much heat was removed from food inside of the refrigerator if it released 380j of energy to the room?

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final