Heat will always flow from a higher temperature body to a lower temperature body. This is a fundamental principle of thermodynamics known as the second law of thermodynamics.

Here's why:

* Thermal equilibrium: Bodies at different temperatures have different levels of internal energy. The hotter body has more energy stored in the motion of its molecules.

* Heat transfer: When two bodies are in contact, energy is transferred from the hotter body to the colder body through collisions between their molecules. This transfer of energy is called heat.

* Entropy: The second law of thermodynamics states that the total entropy of an isolated system can never decrease over time. Entropy is a measure of disorder or randomness. Heat flow from a hotter to a colder body increases the overall entropy of the system, making it more disordered.

Note:

* Heat flow can occur through conduction, convection, or radiation.

* The rate of heat flow depends on the temperature difference, the materials involved, and the area of contact.

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