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Old Saturday, April 24, 2010
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Conduction- energy is transferred by the direct contact of molecules, not by the movement of the material

Example: putting your hand on a stove burner. The amount of energy transferred depends on how conductive the material is. Metals are good conductors, so they are used to transfer energy from the stove to the food in pots and pans. Air is the best insulator, so good insulating products try to trap air and not allow it to move.
Convection- energy is transferred by the mass motion of groups of molecules resulting in transport and mixing of properties

Example: holding your hand over a stove burner. In meteorology, we speak of convection predominantly as that caused by rising currents of warm air. We refer to all other mass motions of air as advection.
Radiation- energy is transferred by electromagnetic radiation

Example: heat felt when standing away from a large fire on a calm night. Everything that has a temperature above absolute zero radiates energy. Radiation is not "felt" until it is absorbed by a substance. It does not require a medium to transfer energy through as do conduction and convection.

question say"A person sitting near the fire receives heat by " so answer seems to be radiation.

i hope its clear now
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