If a cup of coffee is at 90°C and a person with a body temperature of 36°C touches it, how will heat flow between them?
O from the hand to the cup
O from the cup to the hand
Ofrom the cup to the surrounding air
O from the hand to surrounding air

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

Students design a model roller-coaster track. they place a rubber ball at the highest point on the track and let it go. the ball rolls along the track pulled only by the force of gravity. eventually, it comes to a stop. which change to the design will result in the ball moving the greatest distance?

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.