Conduction occurs primarily through which mechanism?

Conduction occurs primarily through which mechanism?

• A. Radiation across space
• B. Movement of molecules in fluids
• C. Direct contact and molecular interaction at a boundary
• D. Evaporation

Answer: (C)

Conduction is heat transfer through direct contact and molecular interaction. When one region is hotter, its particles have more kinetic energy and collide with neighboring particles, passing some energy along. In solids, energy moves via lattice vibrations and, especially in metals, by free electrons quickly sharing energy to cooler parts, all through contact at boundaries or within the material. This is different from radiation, which sends energy as electromagnetic waves across space without contact, and from convection, which relies on bulk fluid motion to transport heat. Evaporation involves a phase change and mass transfer at a surface, not direct contact energy transfer. So the mechanism described is direct contact and molecular interaction at a boundary.

Conduction is heat transfer through direct contact and molecular interaction. When one region is hotter, its particles have more kinetic energy and collide with neighboring particles, passing some energy along. In solids, energy moves via lattice vibrations and, especially in metals, by free electrons quickly sharing energy to cooler parts, all through contact at boundaries or within the material. This is different from radiation, which sends energy as electromagnetic waves across space without contact, and from convection, which relies on bulk fluid motion to transport heat. Evaporation involves a phase change and mass transfer at a surface, not direct contact energy transfer. So the mechanism described is direct contact and molecular interaction at a boundary.