P2 Flashcards
What are the 8 different energy stores?
Thermal Electro-magnetic Electro-static Nuclear Gravitational potential Elastic Chemical Kinetic
What are the two methods of energy transfer?
Heating and working
What are the three ways in which energy can be transferred via heating?
Conduction, Convection and Radiation
What is conduction?
When vibrating particles transfer energy to neighbouring particles
What is convection?
When energetic particles move from hotter to cooler regions
What are the two ways in which energy can be transferred via working?
Mechanically
Electrically
What does it mean to transfer energy mechanically?
An object moving due to a force doing work on it
What does it mean to transfer energy electrically?
A charge doing electrical work against resistance
What is the conservation of energy principle?
Energy can be transferred usefully, stored or dissipitated, but can never be created or destroyed.
How to most fossil fuel power stations generate energy?
1) Fossil fuels burning heats water
2) Water boils and forms steam
3) Steam drives turbine
4) The turbine is connected to an electrical generator which spins a magnet near a coil of wire which induces a voltage which drives a current
What are the pros and cons of wind power?
PROS: - Infinite supply - No fuel cost - No pollution CONS- - Ugly and noisy - Require a lot of space - Only produce energy when its windy- cannot respond to sudden high demand - High set up costs
What are the pros and cons of solar power?
PROS: - Infinite supply - No running costs - No pollution CONS- - High set up costs - Only produce energy when its day- cannot respond to sudden high demand
What are the pros and cons of biofuel power?
PROS:
- Renewable
- When growing plants, they can take CO2 out of the atmosphere (sometimes no net carbon change)
CONS:
- Releases CO2 and Methane when burnt
- High costs
- Lots of land must be cleared- loss of habitat
What are the pros and cons of hydroelectric power?
PROS: - Reliable - Minimal running costs - When demand increases, more water can be let out to generate more energy - Renewable - No pollution when running CONS: - Requires lots of space - Initial high costs - Big environmental impact on ecosystems - Ugly
What are the pros and cons of tidal barrage power?
PROS: - Infinite supply - Reliable - No pollution when running - Low running CONS: - High initial cost - Affects wildlife and boat access - Can spoil the view
How is our energy demands changing?
- The world demand for electricity is increasing due to increasing population, rapidly developing countries, urbanisation and other factor
- Concerns about electricity have led to people making changes in their lives and putting pressure on the government
- Research is being done to find new energy sources
These factors have increased the use of renewable sources
How is electricity distributed?
Via the national grid, to homes and industry alike
What are a.c supplies?
Supplies in which the current is constantly changing direction
What are d.c supplies?
Supplies in which the current is constantly flowing in the same direction
What type of supply is mains supply?
A.c
What type of supply is battery supply?
D.c
What is the live wire?
- Brown
- Carries the voltage in
- 230V
What is the neutral wire?
- Blue
- Carries the voltage out
- 0V
What is the earth wire?
- Green and yellow
- For safety
- Carries the current away if something goes wrong
- 0V
