Page 83 - Science Course 1 (Book 2)
P. 83
Mo8-L6b: What are the Process That Transfer Thermal Energy?
Convection Currents in Earth’s Atmosphere
More thermal energy from the Sun heats the equator Arid regions occur where dry, cool air consistently
than anywhere else on Earth. sink to the surface. This cooler air moves to the
equator as a surface wind.
Most rain forests are at or near the equator,
where rising, moist air results in precipitation.
1. The higher amount of thermal energy at the equator heats the air. The air becomes less dense and rises.
2. Water vapor in the rising air condenses as the air rises and cools. The water falls back to Earth as rain.
3. Cooler air sink back to Earth’s surface where it moves to the equator to replace the less dense, rising air.
SUMMARY
What are the Processes that Transfer Thermal Energy?
Thermal energy can be transferred through When a material is heated, the thermal ener-
radiation, conduction, or convection. gy of the material increases and the material
expands.
Initial
Volume
Initial Length
Final Length
(after heating)
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