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Q & A: heat flow between hot and cold

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Most recent answer: 12/20/2014
Q:
I have been reading about thermodynamics and have a question about the second law which says that heat always flows spontaneously from hotter to colder bodies, and never the reverse, unless external work is performed on the system. My question is, wouldn't the hotter body receive back heat from the colder body in the form of reflection?
- carla (age 62)
rockville, md USA
A:

Yes, heat flows both ways, and not just by reflection. It's just that the spontaneous flow always goes more from hot to cold than from cold to hot.

Mike W.

 


(published on 12/20/2014)

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