When one ball is raised, it acquires potential energy which is then transformed into kinetic energy once the ball is released.

In theory, the total energy should be conserved such that the balls continue in perpetual motion. However, over time, the balls stop moving. Why?

A1500 w electric heater is plugged into the outlet of a 120 v circuit that has a 20 a circuit breaker. you plug an electric hair dryer into the same outlet. the hair dryer has power settings of 600 w, 900 w , 1200 w, and 1500 w. you start with the hair dryer on the 600 w setting and increase the power setting until the circuit breaker trips. under what setting does the circuit breaker trip.