End Of Year 9 Assessments Flashcards
(20 cards)
What is conduction?
The transfer of heat through a solid by vibrating particles passing energy to neighbors.
What is convection?
The transfer of heat in fluids (liquids and gases) where warmer, less dense regions rise and cooler, denser regions sink.
What is radiation?
The transfer of energy by infrared (IR) waves that can travel through a vacuum.
Which surfaces are best at absorbing and emitting radiation?
Dark, matte surfaces.
What is the main reason for energy demand?
To generate electricity and provide transport and heating.
What happens to energy demand during the day?
It increases in the morning and evening due to higher usage.
Name two ways energy demand is met.
By burning fossil fuels or using renewable sources like wind or solar.
Why is it important to balance supply and demand?
To prevent blackouts and ensure a stable energy supply.
How does a fossil fuel power station work?
Burn fuel → heat water → steam turns turbine → turbine turns generator → electricity.
What are the main fuels used in power stations?
Coal, oil, and gas.
What is a base load?
The constant minimum demand for electricity.
What type of power stations provide base load?
Nuclear and some fossil fuel power stations.
What environmental problem is caused by burning fossil fuels?
Air pollution and greenhouse gas emissions.
What is carbon capture and storage (CCS)?
A method to trap CO₂ and store it underground to reduce emissions.
Name a renewable energy source that does not pollute the air.
Solar, wind, or hydroelectric power.
Why are renewable sources better for the environment?
They don’t release harmful gases and are sustainable.
Why can’t we rely only on renewables yet?
They can be unreliable and don’t always produce enough energy.
What is energy security?
Having a reliable and affordable energy supply.
Why do some people oppose wind farms?
They can spoil the landscape and be noisy.
What factors affect the choice of energy sources?
Cost, reliability, environmental impact, and politics.
