Question

The movement of material due to differences in density is called?

Answer 1

The movement of material due to differences in density is called convection.  The differences in density caused by temperature variations result in the the movement of matter and transfer of energy as heat. Warm air is less dense than cold air, and so convection currents can form in the presence of a temperature gradient.

Answer 2

The movement of material due to differences in density is called Convection.