Chapter 38 - Heat Flashcards
What happens to materials when they are heated?
They expand
What happens to materials when they are cooled?
They contract
Above __°C water behaves like other liquids
Above 4°C water behaves like other liquids
Below __°C water behaves oppositely to other liquids
Below 4°C water behaves oppositely to other liquids
What happens to the boiling point of water when you reduce the pressure
The water boils below 100°C
What happens to the boiling point of water when you increase the pressure?
The water boils above 100°C
What is temperature?
The measure of the hotness of a body
What is the unit for temperature?
Degree Celsius °C
What is latent heat?
Latent heat causes a change in state and not a change in temperature
What is latent heat of fusion?
When heat changes a solid to a liquid with no temperature change
What is latent heat of vaporisation?
When heat changes a liquid to a gas with no change in temperature
In what three methods can heat travel?
- Conduction
- Convection
- Radiation
What are insulators?
Materials that are poor conductors of heat
How does heat travel through solids?
Conduction
How does heat travel through liquids?
Convection
True or false? Heat travelling by radiation requires a medium to travel in?
False- radiation does not require a medium
What is heat?
A form of energy
Give examples of heat making things move
- Steam engines
- In power stations, oil and gas are burned to produce heat
- Photosynthesis in plants
Why does the bimetallic stop bend when heated?
This is because materials expand at different rates, therefor when one metal starts to expand it pushes the other on sideways
What can a bimetallic strip be used for?
Switching on and off electrical circuits
