# Physics

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An engineer claims to have measured the characteristics of a heat engine that takes in 130J of thermal energy and produces 40J of useful work.

What is the smallest possible ratio of the temperatures (in kelvin) of the hot and cold reservoirs?

• Physics -

That would be whatever carnot cycle yields an efficiency of 4/13 = 30.8%

1 - T2/T1 = 0.308

T2/T1 = ?

• Physics -

TH/TC=(1)/(1-0.308)

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