External amount of work must be done in order to flow heat from lower temperature to higher temperature. This is according to second law of thermodynamics.
"Heat cannot by itself flow from a body at lower temperature to a body at higher temperature" is a statement or consequence of
Held on 30 Apr 2003 · Verified 6 Jul 2026.
second law of thermodynamics
conservation of momentum
conservation of momentum
first law of thermodynamics
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Work through every JEE Main Thermodynamics PYQ, year by year.