What is the formula used to express the rate of heat transfer from a solid surface?

The formula that describes the rate of heat transfer from a solid surface is typically represented as Q = hAΔT. This equation highlights key variables involved in heat transfer via convection.

In this formula, Q represents the rate of heat transfer (in watts or joules per second), h is the convective heat transfer coefficient (a measure of how effectively heat is being transferred from the surface to the fluid), A is the surface area through which heat is being transferred, and ΔT is the temperature difference between the solid surface and the fluid.

This relationship is particularly relevant in scenarios involving heat exchange between a solid surface and a moving fluid, such as air or water. When evaluating heat transfer, the convective mechanism described by this equation illustrates how surface area and the temperature gradient significantly impact the overall transfer of heat.

The other options refer to different physical phenomena: one relates to the heat capacity of a mass, another pertains to pressure, and the last discusses total heat per unit area. However, none of these options specifically address the rate of heat transfer from a solid surface, which is what the correct answer encapsulates.