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What is convection?
The second way heat travels is by
convection. Convection is the rising of
warm air from an object, such as the
surface of Earth. Convection allows heat
to travel through both gases and liquids,
moving from warmer areas to cooler
areas. It cannot take place in solids.
Convection plays a role in the Earth's
atmosphere, its oceans, and its mantle. Discrete convective cells in the
atmosphere can be seen as clouds, with stronger convection resulting in
Atmospheric circulation is the
large-scale movement of air, and
the way thermal energy is
distributed on the surface of the
Earth. The large-scale structure of
the atmospheric circulation varies
from year to year, but the basic
structure remains fairly constant.
Convection currents also
affect the way the plates move
on earth. When convection
currents diverge near the
crust the plates move apart.
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When they converge the plates move towards each other.
What is conduction?
Conduction is the flow of heat through a solid. When you walk on a hot
sidewalk, the concrete warms--or burns--your feet through conduction.
When a warmer substance with quickly moving molecules (the sidewalk)
comes into contact with a cooler substance with slowly moving molecules
(your bare feet), the faster molecules bump into the slower ones and
makes them move faster, too.…read more
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What is radiation?
Radiation is energy transmitted
in the form of electromagnetic
waves that travel through the
vacuum of space at the speed of
light. . This is why we can still
feel the heat of the Sun,
although it is 150 million km
away from the Earth. Infrared
radiation consists of
wavelengths that are shorter
than radio waves but longer
than visible light. Infrared radiation takes the form of heat. These heat rays
are much like light rays except that we cannot see them.…read more