Energy Flashcards
Energy stores and systems
What is specific heat capacity?
The amount of energy needed to raise the temperature of a 1kg substance by 1 degree C
Energy stores and systems
What is power?
The rate at which energy is transferred
Energy transfers in systems
State the law of energy conservation.
Energy cannot be created or destroyed, but can be transferred from store to store.
Energy transfers in systems
What is conduction?
Conduction is the heat transfer between solids
Energy transfers in systems
What is convection?
Convection is the heat transfer between liquids or gases
Efficiency
How can efficiency be increased?
- Reducing waste output (lubrication, thermal insulation etc.)
- Recycling waste output (e.g recycling thermal waste as input energy)
Efficiency
What are three ways of reducing heat loss in a building.
- Double glazing windows
- Loft and wall insulation
- Thicker walls
Efficiency
How can the efficiency of a mechanical machine with moving parts be improved?
Lubricate any moving parts to reduce friction and therefore energy loss due to heating.
National and Global Energy Resources
What is a renewable energy resource?
An energy source that can be replenished as it is being used up.
National and Global Energy Resources
Give four examples of renewable energy resources.
- Wind energy
- Hydro-Electricity
- Tidal energy
- Solar energy
National and Global Energy Resources
Give an example of a non-renewable energy resource.
Fossil Fuels
National and Global Energy Resources
State two disadvantages of using renewable energy resources
- Supply is uncertain
- Generating power through other means is more efficient and economically beneficial
National and Global Energy Resources
Explain the environmental impacts of burning fossil fuels.
- Carbon dioxide causes global warming
- Sulphur dioxide leads to acid rain
National and Global Energy Resources
State three advantages of using fossil fuels
- Reliable
- Can produce large amounts
- Still relatively abudant, so cost effective
National and Global Energy Resources
State three advantages of nuclear power.
- very large amounts of energy for relativley small quantities of fuel
- doesn’t release greenhouse gases
- low fuel costs
National and Global Energy Resources
State three disadvantages of nuclear power.
- Produces nuclear waste which is harmful to humans
- non-renewable
- risk of nuclear accidents - fatal consequences on humans and the environment
National and Global Energy Resources
How does hydroelectric power produce electricity?
- water collects behind a dam
- when it is released, the water turns a turbine
- the turbine turns a generator which generates electricity
National and Global Energy Resources
What are some disadvantages of using biofuels?
- when plants are burned or decay, they release co2
- must destroy land to grow them
- growing biofuels reduces the land available for growing food
National and Global Energy Resources
What are the advantages of tidal energy?
- don’t produce greenhouse gases
- they are quite reliable - tides happen twice a day
- cheap as tides are natural
National and Global Energy Resources
What are the disadvantages of hydroelectric power?
- dam may cause flooding
- can be expensive
National and Global Energy Resources
What are some advantages of solar panels?
- don’t harm the environment
- renewable
- they can be used in remote areas
National and Global Energy Resources
Give examples of social factors which may act as a deterrent for certain types of energy production.
- visual pollution
- sound pollution
