Thermal energy moves throughout a system by a convection current. The difference in densities between warmer and cooler fluid or air cause the current to happen.
Ex.1) Warm water at the bottom of a pan is less dense than the colder water at the top, then the warm water is pushed to the top, and the cold to the bottom. This keeps happening, making the current.
Ex.2) Currents happen in the atmosphere. Warm air from the equator moves toward the poles, while the poles cold air moves toward the equator.
Ex.1) Warm water at the bottom of a pan is less dense than the colder water at the top, then the warm water is pushed to the top, and the cold to the bottom. This keeps happening, making the current.
Ex.2) Currents happen in the atmosphere. Warm air from the equator moves toward the poles, while the poles cold air moves toward the equator.
