Convection - Animated Science

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Transcript Convection - Animated Science

Convection
Ashfield Direct Learning
Ks4 Energy
By Adam Harland
What is convection?
 This is the way heat is transferred in
liquids and gases.
 It depends on, in general, fluids expand
when heated and become less dense.
 This is a domestic hot water tank.
Convection Currents
 A current, called a convection
current becomes present in the
liquid If heat is supplied.
 Cooler liquid falls.
 Warmer, less dense liquid rises.
 The cycle continues as the heat is
supplied
Convection Currents
 The Earth’s lithosphere (the
crust) is cracked into a
number of large pieces
(tectonic plates) which are
constantly moving.
 This is as a result of
convection currents within
the Earth’s mantle driven by
heat released by natural
radioactive processes.
Radiators
 The heat from a radiator
causes the warm air to
rise and as the air rises
then it cools and
becomes denser.
 The cool air falls and
replaces the warm air
which is rising.
 And the cycle continues
until the radiator cools.
Conclusion of convection
In conclusion convection is:
 The way heat is transferred in liquids and gasses
 It depends on, in general, fluids or gases expand
when heated and become less dense.