Types of Energy Transfer: Conduction, Convection & Radiation

Conduction

▪ Conduction involves objects in direct contact. ▪ The transfer of energy as heat occurs between particles as they collide within a substance or between two objects in contact. ▪ All materials do not conduct heat energy equally well. ▪ Poor conductors of heat are called insulators. ▪ The energy transfers from an area of higher temperature to an area of lower temperature. ▪ For example, if a plastic spoon and a metal spoon are placed into a hot liquid, the handle of the metal spoon will get hot quicker than the handle of the plastic spoon because the heat is conducted through the metal spoon better than through the plastic spoon.

Convection

▪ Convection is the transfer of energy as heat by movement of the heated substance itself, as currents in fluids (liquids and gases). ▪ In convection, particles with higher energy move from one location to another carrying their energy with them. ▪ Heat transfer occurs when particles with higher energy move from warmer to cooler parts of the fluid. ▪ Uneven heating can result in convection, both in the air and in water. This causes currents in the atmosphere (wind) and in bodies of water on earth which are important factors in weather and climate.

Radiation

▪ Radiation is the transfer of energy through space without particles of matter colliding or moving to transfer the energy. ▪ This radiated energy warms an object when it is absorbed. ▪ Radiant heat energy moves from an area of higher temperature to an area of cooler temperature.