Which statement best describes the direction of heat transfer between two bodies with a temperature difference?

Which statement best describes the direction of heat transfer between two bodies with a temperature difference?

• A. From cooler to hotter
• B. From unpredictable directions
• C. It never transfers
• D. From hotter to cooler

Answer: (D)

Heat flows from higher temperature to lower temperature. When two bodies differ in temperature, thermal energy moves from the hotter one to the cooler one until both reach the same temperature. This is why the statement that heat transfers from hotter to cooler is the best description. The other ideas don’t fit: heat moving from cooler to hotter would require external energy to reverse the natural direction, heat never transferring ignores the driving force of a temperature difference, and heat would not move in unpredictable directions—the gradient determines the flow. In everyday terms, think of a hot surface warming a cooler object: energy moves from the hot body to the cooler one until thermal equilibrium is reached.

Heat flows from higher temperature to lower temperature. When two bodies differ in temperature, thermal energy moves from the hotter one to the cooler one until both reach the same temperature. This is why the statement that heat transfers from hotter to cooler is the best description. The other ideas don’t fit: heat moving from cooler to hotter would require external energy to reverse the natural direction, heat never transferring ignores the driving force of a temperature difference, and heat would not move in unpredictable directions—the gradient determines the flow. In everyday terms, think of a hot surface warming a cooler object: energy moves from the hot body to the cooler one until thermal equilibrium is reached.