Convection transfers heat through the movement of fluids (liquids or gases) caused by temperature differences within the fluid. When a part of the fluid is heated, it becomes less dense and rises, while cooler, denser fluid moves in to replace it. This creates a circulation pattern known as a convection current, which transports heat from the warmer region to the cooler region. More specifically:

• Heat transfer by convection involves both conduction (heat diffusion between molecules) and advection (bulk movement of the fluid carrying heat)

• As the fluid near a heat source warms up, it expands and becomes less dense, causing it to rise. Cooler, denser fluid then moves in to take its place, continuing the cycle and transferring heat throughout the fluid

• This process can be natural (driven by buoyancy forces due to density differences from temperature changes) or forced (induced by external means like a pump or fan)

• The rate of heat transfer by convection depends on factors such as the temperature difference, fluid properties, fluid velocity, and surface area involved

In everyday examples, convection explains how warm air rises from a radiator and cooler air moves in to be heated, creating a circulation that warms a room. Similarly, your body loses heat by convection when cooler air moves past your skin, absorbing your body heat and rising away

. In summary, convection transfers heat by the bulk movement of warmer, less dense fluid rising and cooler, denser fluid sinking, creating a continuous circulation that transports thermal energy from hot to cold regions within the fluid.