Which of the following factors does NOT drive convection?

Convection is primarily driven by the movement of fluid due to temperature differences, which create variations in density, leading to buoyancy effects. When a fluid is heated, it becomes less dense and rises, while cooler, denser fluid sinks. This cycle establishes convection currents.

While temperature differences and their subsequent effects on density are crucial for driving convection, pressure differences, especially in fluids, can also influence the movement, such as in atmospheric convection where pressure gradients affect air flow.

Magnetic forces, however, do not directly drive convection. While they can have an effect on charged particles and plasma, in the context of convection in fluids like air or water, magnetic forces do not initiate the process of convection. Hence, the factor that does not drive convection is the presence of magnetic forces.