Name the three basic modes of heat transfer.

• A. Conduction, reflection, radiation
• B. Conduction, convection, radiation
• C. Conduction, convection, conduction
• D. Radiation, convection, conduction

Answer: (B)

Heat moves mainly in three ways: conduction, convection and radiation. Conduction is energy transfer through direct contact or through a substance as particles collide and pass energy along; it’s why a metal spoon gets hot when its end is in hot liquid. Convection happens when a fluid (liquid or gas) moves as a result of temperature differences—hot fluid rises, cooler fluid moves in to take its place, creating circulating currents, like warm air from a heater or the churning in boiling water. Radiation is heat transfer by electromagnetic waves; it can occur through empty space, so you can feel warmth from the sun or a fire without touching them.

One option includes a term that isn’t a heat-transfer method, while another option repeats a mode and omits one of the three. The correct trio to name is conduction, convection and radiation.