A 2400 pound car ascends a 10 degree slope at 30 miles per hour. If the overall efficiency is 70 percent, the power output at 70 percent efficiency is 47.7 horsepowers.(adsbygoogle = window.adsbygoogle || []).push({});

By the formula, Power=(force)(velocity) with 1 horsepower=550 ft*lb/s , the power output at 70% efficiency is 23.38 horsepowers.

Can someone explain why it should be 47.7 horsepowers?

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# Homework Help: Power output of a car's engine

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