Heat dissipation from heat sink mainly takes place by

Heat dissipation from a heat sink mainly takes place by three mechanisms: conduction, convection, and radiation. Among these, convection is typically the primary mechanism in most applications, where heat is transferred from the heat sink surface to the surrounding air or fluid. Conduction occurs as heat moves through the material of the heat sink itself, and radiation is a lesser factor as it depends on the temperature difference and surface area.

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