1 Energy Transfer by Heating Flashcards
What substances can convection happen in?
Convection can happen in liquids and gases.
What is a fluid? (JR)
A liquid or a gas
What makes metals efficient conductors? (JR)
Delocalised (Free) Electrons
What is the definition of specific heat capacity (JR)
The energy required to raise 1kg of a substance by 1°C
Name the four types of heat transfer
Conduction
Radiation
Convection
Evaporatuon
What type of radiation do all hot objects emit?
Infra-red radiation.
What are the best absorbers of thermal radiation?
Black, dull surfaces.
How does heat pass through a single pane of window glass?
By conduction and radiation
What is a property of a liquid?
.
They cannot be compressed because their particles are close together.
What type of surface emits the most heat, in thermal radiation?
Matte/Dull black
Explain the process of convection.
As a fluid is heated, the particles gain heat energy which means the spread out, becoming less dense, lighter and so they rise. As the particles begin to cool they get closer together and therefore denser and heavier, so they sink.
What is a vacuum? Give an example.
An area with NO particles.
Space would be an example.
Why would it be best for someone in a hot country to wear white rather than black?
White absorbs the least heat, keeping them cooler.
Explain the process of conduction.
One particle gains heat energy and begins to vibrate. The vibrating particle then collides with the next particle, transferring this heat energy along.
