AIPMT PRELIMS 2000 Physics Convection MCQ Question

Gravitational force plays a crucial role in the process of convection, which is the transfer of heat through the movement of fluids. In convection, warmer, less dense fluid rises while cooler, denser fluid sinks, creating a circulation pattern. This movement is driven by the force of gravity acting on the different densities of the fluid.

Option A, stirring of liquid, does not specifically require gravitational force; it can be achieved through mechanical means.

Option C, conduction, is the transfer of heat through direct contact and does not involve fluid movement or gravitational force.

Option D, radiation, is the transfer of energy through electromagnetic waves and does not require a medium or gravitational force.

Thus, the correct answer is B) Convection, as it is directly influenced by gravitational force.