In classical thermodynamics, if we dissipated the kinetic energy of an object as thermal energy, then we would increase the entropy.(adsbygoogle = window.adsbygoogle || []).push({});

However, let's say we took 90% of some thermal energy in a reservoir, and converted it into work, and 10% of that is converted back into thermal energy after 1 minute is passed. This would mean that 81% of the thermal energy has been converted into work.

If we dissipate work as heat, entropy increases. So what happens if we convert heat into work? Shouldn't the opposite occur - a decline of entropy?

I think we should have a sum of changes, an entropy increase in excess of a subsequent decrease. Is this the correct view?

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# Entropy changes: Thermal energy to work and (some) back to Thermal energy

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