A less obvious example is thermal radiation from the human body. An obvious example is the warming of Earth by the Sun.

Heat transfer by radiation occurs when microwaves, infrared radiation, visible light, or another form of electromagnetic radiation is emitted or absorbed.

This type of transfer takes place in a forced-air furnace and in weather systems, for example.

Convection is the heat transfer by the macroscopic movement of a fluid.

(The matter is stationary on a macroscopic scale-we know that thermal motion of the atoms and molecules occurs at any temperature above absolute zero.) Heat transferred from the burner of a stove through the bottom of a pan to food in the pan is transferred by conduction.

Conduction is heat transfer through stationary matter by physical contact.

Yet every heat transfer takes place by only three methods: So many processes involve heat transfer that it is hard to imagine a situation where no heat transfer occurs.

It may occur rapidly, as through a cooking pan, or slowly, as through the walls of a picnic ice chest. Whenever there is a temperature difference, heat transfer occurs. Just as interesting as the effects of heat transfer on a system are the methods by which it occurs. Solve problems using the formulas for conduction and radiation.

Solve problems on the relationships between heat transfer, time, and rate of heat transfer.Explain some phenomena that involve conductive, convective, and radiative heat transfer.By the end of this section, you will be able to:

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