In what direction does heat flow? Why do particles of matter transfer thermal energy in this direction?

Step 1: Define the Problem

Identify the direction of heat flow and understand why particles transfer thermal energy in that direction.

Step 2: Break Down the Problem

1. Determine the general principle governing heat flow.
2. Explain the behavior of particles in relation to thermal energy transfer.

Step 3: Apply Relevant Concepts

• Heat Flow Direction: Heat always flows from a region of higher temperature to a region of lower temperature.
• Particle Behavior: Particles in a substance move more vigorously at higher temperatures, transferring energy to less energetic particles at lower temperatures.

Step 4: Analysis, Verify and Summarize

• Analysis: Heat transfer occurs due to the kinetic energy of particles. In a hotter region, particles have higher kinetic energy and collide with particles in a cooler region, transferring energy.
• Verification: This principle is consistent with the second law of thermodynamics, which states that energy spontaneously spreads from regions of higher concentration to lower concentration.

Final Answer

Heat flows from a region of higher temperature to a region of lower temperature because particles transfer thermal energy through collisions, moving from areas of higher kinetic energy to areas of lower kinetic energy.