:( if a 20 n object has been lifted 5 meters above the ground, how much gravitational potential energy does it have? a. 980 n b. 100 j c. 980 j d. 100 n

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?

A30 kg weight lies on top of a massless piston of area a = 0.01 m2 the exterior air is at a (constant) p =1 atm and t = 27 c. the interior gas is 0.4 moles of (ideal) n2 and it has initial temperature 27.00 degrees c. 1. what is the initial pressure in the interior? a. 29.4 kpa b. 130.7 kpa c. 101.3 kpa the next three questions concern what happens when an amount of heat q is slowly added to the interior, raising the piston by 1 mm and raising the interior temperature to 27.40 c

A100-watt light bulb illuminates a solar cell. the electricity from the solar cell operates a water pump that delivers 1 watt of power. what is the efficiency of the system?