Hi, i just want to check my reasoning on this problem.(adsbygoogle = window.adsbygoogle || []).push({});

A working substance is taken around a closed cycle that involves performing some external work. It absorbes heat Q1 = 1000J from a resevoir at T1 = 1000K, and heat Q2 = 2000J from a resevoir at T2 =2000K. The only other exchange of heat is with a resevoir at T3 = 300K.

What is the minimum heat that must have been transferred from the substance to the resevoir at T3 ( explain your reasoning)?

Now i think the minimum heat is 600J, as the entropy change of the system must be >= 0, and we must have heat rejection otherwise we'd violate the 2nd law. Is this ok?

Thanks

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# Homework Help: Entropy problem (i think)

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