Which term describes heat transfer through space by electromagnetic waves?

Which term describes heat transfer through space by electromagnetic waves?

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

Answer: (B)

The idea tested is that heat transfer through space happens by electromagnetic waves, which is called radiation. In the vacuum of space there’s no solid or fluid to conduct heat or to circulate it by convection, so those methods can’t operate there. Radiation travels as photons and can move through empty space, letting energy from the Sun reach planets. Conversely, conduction requires direct contact between particles, and convection needs a moving fluid to carry heat, while evaporation is a phase-change process involving energy to change a liquid to gas rather than a general space-wide transfer mechanism. So the term for heat transfer through space by electromagnetic waves is radiation.