Question

what happens during heat transfer?
heat always flows from warm to hot.
heat always flows from warm to cool.
heat always flows from cool to warm.

Explanation:

Heat transfer occurs due to a temperature difference. According to the second law of thermodynamics, heat naturally moves from a region of higher temperature (warm) to a region of lower temperature (cool) until thermal equilibrium is reached. This is a fundamental principle in thermodynamics.

Answer:

Heat always flows from warm to cool.