Heat transfer refers to the process of moving heat energy from one place to another. It can happen when there is a difference in temperature between two objects or substances. The heat can be transferred through three methods: conduction (when it travels through direct contact), convection (through the movement of liquid or gas), or radiation (when it travels through electromagnetic waves, like how the Sun warms the Earth). So basically,
heat transfer is the movement of heat from a warmer object to a cooler object.
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