An engine extracts 452.8kj of heat from the burning of fuel each cycle, but rejects 266.7 kj of heat (exhaust, friction, etc) during each cycle. what is the thermal efficiency of the engine?

A1,200 kg car is accelerated at 3.7 m/s2. what force was needed to produce this acceleration? a. 4,440 n b. 324.3 n c. 4,388 n d. 304.3 n

Choose the most likely outcome of this scenario: jen decided to go bike riding without a helmet. while no one is around during her ride, she is thrown from her bike when her wheel goes into a pothole. she is not injured, but she is terrified to get back on her bike. what happens next? a. her physical health is affected even though she wasn't hurt. b. her mental and emotional health are affected because she is afraid to get back on her bike. c. her social health is affected because she is worried her friends saw the fall. d. her overall health is not affected at all by her fall.

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?