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Convection in the home


The following list gives you some idea where convection is important in the home.

Cooking in hot water

Christmas decorations – a candle under a mobile

Convector heater – hot air rises through the heater

Central heating boiler

Immersion heater at the bottom of a hot water tank

Kettle with the element at the bottom

Cold air convecting off the outside of windows

Air movement in cavity walls before putting foam insulation in

Radiators – they work by air convection and not by radiation

Chimney to an open fire or a boiler

Lava lamp – if you know what that is

Chest freezer – it does not matter too much if you open the top
for a little while because the colder air will sink to the bottom of the freezer.

A few notes on convection:
1. A fluid (liquid or gas) heats up
2. The fluid expands as it heats up
3. The density of the fluid therefore goes down
4. The hot fluid rises up through the colder fluid – until it floats on liquid of a higher density
 

A VERSION IN WORD IS AVAILABLE ON THE SCHOOLPHYSICS USB
 
 
 
© Keith Gibbs 2020