Which statement is NOT true about conduction?

Which statement is NOT true about conduction?

• A. It requires direct contact between materials.
• B. High thermal conductivity materials transfer heat faster.
• C. It can occur without a medium.
• D. It is influenced by the temperature difference between materials.

Answer: (C)

Conduction is the transfer of thermal energy by direct contact through interactions between neighboring particles or free electrons within a material or at the boundary between touching materials. When there’s a temperature difference, energy moves from the hotter region to the cooler one as particles collide and energy is carried by phonons or electrons. This process relies on matter to transfer energy, so conduction occurs in solids, liquids, and gases where particles are in contact. In a vacuum there are no particles to collide, so conduction cannot happen there; heat transfer in a vacuum occurs mainly by radiation. Materials with high thermal conductivity, like metals, transfer heat more rapidly under the same temperature difference because their particles interact more efficiently. The rate of conduction also depends on how large the temperature difference is—the greater the difference, the faster the transfer. Therefore, the idea that conduction can occur without a medium isn’t correct.

Conduction is the transfer of thermal energy by direct contact through interactions between neighboring particles or free electrons within a material or at the boundary between touching materials. When there’s a temperature difference, energy moves from the hotter region to the cooler one as particles collide and energy is carried by phonons or electrons. This process relies on matter to transfer energy, so conduction occurs in solids, liquids, and gases where particles are in contact. In a vacuum there are no particles to collide, so conduction cannot happen there; heat transfer in a vacuum occurs mainly by radiation. Materials with high thermal conductivity, like metals, transfer heat more rapidly under the same temperature difference because their particles interact more efficiently. The rate of conduction also depends on how large the temperature difference is—the greater the difference, the faster the transfer. Therefore, the idea that conduction can occur without a medium isn’t correct.