How does density play a part in convection currents? Explain.

(I NEED THE ANSWER ASAP)

Convection is heat transfer due to a density differential within a fluid

Example:

The current begins when the air over the hot sand is heated and begins to rise because of its lowered density. Air from above the ocean is colder and more dense. This cooler air takes the place of the rising hot air from over the sand

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