Convection Flashcards
What are gases and liquids free to do?
Slosh about.
Allows them to transfer heat by convection.
More effective process than conduction.
The convection of heat is only what?
Liquids.
Gases.
Define convection.
Convection occurs when the more energetic particles move from the hotter region to the cooler region, taking their heat energy with them.
Convection is how what works.
Give examples.
Immersion heaters in kettles and hot water tanks.
Why can’t convection occur in solid?
Because the particles can’t move.
What are convection currents all about?
Changes in density.
Immersion heater example;
Heat energy is transferred from where?
The heater coils to water by conduction.
Immersion heater example;
What happens to the particles near the coils?
Get more energy.
Start moving faster.
Immersion heater example;
The particles getting faster means what?
There’s more distance between them.
Water expands becomes less dense.
Immersion heater example;
The reduction in density means what?
The hotter water tends to rise above the denser cooler water.
Immersion heater example;
As the hot water rises what happens?
It displaces the colder water out of the way.
Sinking towards the heated coils.
Immersion heater example;
The colder water is then heated by what?
The coils and rises.
Immersion heater example;
What do you end up with?
Convection currents going up, round and down
Circulating the heat energy through the water.
Where is convection most efficient?
In roundish or squarish containers.
Allow the convection currents to work best.
The hot water rises you only get convection currents where?
In the water above the heater.
