A hospital has a back-up generator to power the medical devices in case of a power failure. Which of the following is the most likely source of mechanical
energy for the generator?

A. Burning coal

B. Sunlight

C. Gasoline or diesel fuel

D. Falling water

Which of the following represents an upside-down image?

A175 g lump of molten lead at its melting point (327 c) is placed into 55.0 g of water at 20.0 c. the specific heat of lead is 130.j/kg c and the hf of lead is 20,400 j/kg. when the lead and the water have reached equilibrium, what is the temperature of the mixture?

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?