heat transfer conduction, convection, radiation. three main processes of heat transfer conduction ...

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Heat TransferConduction, Convection, Radiation

Three Main Processes of Heat TransferConductionConvectionRadiation

ConductionTransfer of heat between substances or objects

that are in direct contact with each other.Heat travels from object at higher temperature to

object at lower temperature. If it feels hot, the heat is transferring into you

from the object. If it feels cold, then heat is transferring from you

into the object.Heat is transferred from the faster moving particles

to the slower moving particles by colliding. This continues until both objects have reached the same temperature, thermal equilibrium.

ConductionConduction occurs in all states of matter, but works

best in solids since the particles are closer together.

Metals are especially good conductors of heat.

ConvectionHeat transfers through the motion of a fluid.The hotter fluids rise and the cooler fluids fall due to the difference in densities.

Occurs in a gas, liquid, or plasmaThe rising and falling motion of the fluid is called a convection current.

Radiation The transfer of heat through electromagnetic waves. Electromagnetic waves carry a certain amount of

energy that is directly proportional to the frequency of the wave. Lower frequency waves have less energy, and higher

frequency waves have more energy The main source of heat through radiation of Earth is

the Sun. The heat is transferred to the molecules in the air,

water, and land. The greenhouse effect occurs when the Earth’s

atmosphere absorbs and traps thermal radiation from the Earth’s surface.

This can also be seen on a smaller scale with a greenhouse or a Crookes radiometer.

Page 260 in the bookYou need to transfer the chart and the picture of the fire into your journal.

The picture needs to be labeled exactly as you see it.

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