A 20% efficient real engine is used to speed up a train from rest to 5 m/s. It is known that an ideal (Carnot) engine using the same cold and hot reservoirs would accelerate the same train from rest to a speed of 6.5 m/s using the same amount of fuel. The engines use air at 300 K as a cold reservoir. Find the temperature of the steam serving as the hot reservoir.(adsbygoogle = window.adsbygoogle || []).push({});

I don't know how the velocity comes into play in order to get the temperature of the steam serving as the hot reservoir. I know that the formula for efficiency is

[tex] e = \frac {W_{eng}} {|Q_{h}|} [/tex].

Any help would be great! thx! :)

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# Homework Help: Need help with Heat Engines

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