Convection occurs all around us
It can be seen in simple everyday processes, such as heating water on a stove, or in larger natural ones, such as volcanic eruptions.
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Transcript
Convection occurs when heat is transferred by the movement of liquids or gases. For example, when water is heated on a stove, heat from the stove transfers to the water at the bottom of the kettle.
The water at the bottom expands and becomes lighter as it heats. The heated water molecules then rise to the top of the kettle, causing cooler water molecules to sink to the bottom.
There, the cooler water is heated--and then rises. The process repeats until all the water is the same temperature.
Convection currents can occur in simple environments such as a fish tank or a room.
They also occur in larger environments, such as Earth’s oceans, atmosphere, or core.
Volcanic eruptions are caused by convection currents inside Earth.
For example, heat from deep within Earth’s core flows – or is transferred – to the bottom layer of mantle rock. The hot mantle rock softens and moves up, pushing cooler rock downward and forcing magma to the surface, where it exits an active volcano as lava.
The water at the bottom expands and becomes lighter as it heats. The heated water molecules then rise to the top of the kettle, causing cooler water molecules to sink to the bottom.
There, the cooler water is heated--and then rises. The process repeats until all the water is the same temperature.
Convection currents can occur in simple environments such as a fish tank or a room.
They also occur in larger environments, such as Earth’s oceans, atmosphere, or core.
Volcanic eruptions are caused by convection currents inside Earth.
For example, heat from deep within Earth’s core flows – or is transferred – to the bottom layer of mantle rock. The hot mantle rock softens and moves up, pushing cooler rock downward and forcing magma to the surface, where it exits an active volcano as lava.