A heat engine operating between a pair of hot and cold reservoirs with respective temperatures of 500 K and 200 K will have what maximum efficiency? A) 60%
B) 50%
C) 40%
D) 30%

Sawyer is studying diffraction. he draws a diagram of a plane wave to show how light waves travel. which best describes sawyer’s error? the wave fronts should be perpendicular to the direction in which the waves move. the arrow showing the direction of movement of the waves should be pointing to the left. the arrow showing the direction of movement of the waves should be pointing downward. the wave fronts should be both parallel and perpendicular to the direction in which the waves move.

Amira pulls a 3 pound wagon 4 feet. how much work has she done?

The voltage applied across a given parallel-plate capacitor is doubled. how is the energy stored in the capacitor affected?