Which heat transfer mode is primarily described by energy transfer through electromagnetic waves?

Which heat transfer mode is primarily described by energy transfer through electromagnetic waves?

• A. Conduction
• B. Convection
• C. Radiation
• D. Evaporation

Answer: (C)

Radiation is energy transfer by electromagnetic waves. It doesn’t need a medium and can travel through vacuum, which is why heat from the sun reaches Earth and why a hot object can warm you even when there’s no touch or air between them. The other modes rely on matter: conduction transfers energy through direct molecular interactions, and convection moves heat with the bulk motion of a fluid. Evaporation is a phase change that involves latent heat, not a propagation of energy via waves. So energy transfer through electromagnetic waves is the radiation mode.

Radiation is energy transfer by electromagnetic waves. It doesn’t need a medium and can travel through vacuum, which is why heat from the sun reaches Earth and why a hot object can warm you even when there’s no touch or air between them. The other modes rely on matter: conduction transfers energy through direct molecular interactions, and convection moves heat with the bulk motion of a fluid. Evaporation is a phase change that involves latent heat, not a propagation of energy via waves. So energy transfer through electromagnetic waves is the radiation mode.