A lawn mower has a 6-horsepower engine (1 HP = 750 W). If the engine has an efficiency of 20%, and the throttle is such that the engine cycles 10 times a second, the heat that is expelled in one cycle is

a. 1 800 J
b. 2 000 J
c. 2 200 J
d. 2 400 J
e. 2 250 J


A

Physics & Space Science

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