What direction does heat flow?

What direction does heat flow?

• A. From cold to hot
• B. In all directions randomly
• C. Only within gases
• D. From hot to cold

Answer: (D)

Heat flows from higher temperature to lower temperature. When two bodies touch or interact, the faster, higher-energy particles in the hotter object transfer energy to the cooler one, cooling the hot body and warming the cool one, until they share the same temperature. This direction holds across all modes of heat transfer: conduction in solids, convection in fluids, and radiation through space. The net transfer is always downhill in temperature, not from cold to hot, not random, and not limited to gases.

Heat flows from higher temperature to lower temperature. When two bodies touch or interact, the faster, higher-energy particles in the hotter object transfer energy to the cooler one, cooling the hot body and warming the cool one, until they share the same temperature. This direction holds across all modes of heat transfer: conduction in solids, convection in fluids, and radiation through space. The net transfer is always downhill in temperature, not from cold to hot, not random, and not limited to gases.