Answer:
Convection occurs when thermal energy is transferred by the movement of fluid particles.
Step-by-step explanation:
Transfer of heat energy by the movement of fluid particles is called convection. Convection takes place in liquids and gases due to kinetic energy. When heat is provided to liquids and gases they expand and move faster.
Molecules with higher kinetic energy become less dense and rise up to the surface of liquid, whereas molecules with lower energy move towards the bottom. This up and down movement of molecules causes convection currents in fluids.