Middle School Physical Science: Thermal Energy - Transfer of Thermal Energy — Flashcards

There are three types of thermal energy transfer: conduction, radiation, and convection.
 

Convection is the transfer of thermal energy by particles moving through a fluid. Particles transfer energy by moving from warmer to cooler areas. That's how energy is transferred through soup in a pot on a hot stove. Particles of soup near the bottom of the pot get hot first. They have more energy so they spread out and become less dense. With lower density, these particles rise to the top of the pot. By the time they reach the top of the pot, they have transferred their thermal energy and cooled. They have less energy to move apart, so they become denser. With greater density, the particles sink to the bottom of the pot, and the cycle repeats. This loop of moving particles is called a convection current. Convection currents move thermal energy through many fluids, including molten rock inside Earth, water in the oceans, and air in the atmosphere.