A 3.25 * 10(adsbygoogle = window.adsbygoogle || []).push({}); ^{3}-kg aircraft takes 12.5 min to achieve its cruising altitude of 10.0 km and cruising speed of 850 km/h. If the plane's engines deliver, on the average, 1500 hp of power during this time, what is the efficiency of the aircraft engines?

I initially believed the power out would be: (Kinetic energy + Potential energy)/Time

And efficiency would be 1500hp/power out. But after my calculations, I got 14.6% efficiency, when it should be 48.7% efficiency.

What did I do wrong?

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# Homework Help: Power efficiency problem

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