Energy Flashcards
(28 cards)
What does the law of conservation of energy state?
Energy cannot be created or destroyed, only transferred
Total energy before = total energy after
What are the ways of transferring energy?
- Light
- Sound
- Electricity
How is temperature measured?
In degrees Celsius (°C)
What does temperature measure?
Average energy
What does thermal energy measure?
Total energy
Which has more thermal energy: a warm bath or a heated kettle?
A warm bath
What happens to particles as we heat solids, liquids, and gases?
They gain more kinetic energy and vibrate more or faster
What does the energy needed to heat an object depend on?
- Mass
- Material
- Temperature rise
What is equilibrium in the context of thermal energy?
When objects have the same thermal energy
What do renewable resources produce when built?
Greenhouse gases
Name three examples of renewable energy sources.
- Wind
- Solar
- Hydroelectric
What are the three methods of thermal energy transfer?
- Conduction
- Convection
- Radiation
In which state of matter does conduction occur?
Solids
What occurs during convection?
The part in contact with the heat source gets hotter, causing particles to move faster and become further apart
What is a convection current?
The cycle of hot parts rising and cooler parts falling in liquids or gases
What do fossil fuels produce when burned?
Greenhouse gases, such as carbon dioxide
What are non-renewable resources?
Resources that cannot be reused and will eventually run out
Name three examples of non-renewable resources.
- Coal
- Oil
- Gas
What is the energy measurement unit for food and fuels?
Joules (J)
What is power defined as?
The rate of energy transfer
How are energy bills measured?
In kilowatt hours (kWh)
How do you convert kWh to joules?
Convert the time to seconds and multiply by the energy in joules per second
What is the formula for work done?
Work done (J) = force (N) x distance (m)
What is infrared radiation?
Energy transfer without particles; it is a wave
