Heat Energy Is Transferred Through Conduction and Convection Flashcards
What is heating by conduction?
Heat transfer via conduction is the transfer of thermal energy from matter that is warmer to matter that is colder. This occurs when 2 objects come into contact.
What is thermal equilibrium?
When 2 objects reach thermal equilibrium, it means they can no longer exchange energy since they’re the same temperature.
What is heating by convection?
Heating via tiny currents, AKA convection currents that carry thermal energy.
What states of matter does thermal energy transfer to by convection?
Liquids and gases.
What’s a convection current?
A movement within a liquid or gas.
Why are liquids heated from below?
Liquids are heated from below because most of the energy transfer in liquids and gases takes place via convection.
Give an example of convection.
The sun heats the ground and through conduction heats the air near it. The warmed air is less dense than the cool air above and rises taking the thermal energy with it. This distributes the warmth within many layers of the air, not just one.
Give an example of conduction.
Gas is burned on a stove and thermal energy is released, the hot particles in the flame move quickly and bump into the atoms of the cold metal saucepan. Energy passes to the slowly vibrating atoms so they vibrate faster. The quickly vibrating atoms in the saucepan bump into other nearby metal atoms, transferring energy to them, hence heating the saucepan. When the sauce heats up the energy is transferred to the water.
What is a conductor?
Any material that allows thermal energy to travel through it.
Give an example of a conductor.
Any metals.
What is a insulator?
Any material that slows down the transfer of thermal energy.
Give an example of an insulator.
Blankets, jumpers and socks.
Do insulators only keep heat in?
No, they also keep heat out. For example, during summer the roof and walls of a house keeps the heat out.
