Energy Flashcards
What are the 10 stores of energy?
Magnetic potential energy Kinetic energy Thermal energy Light energy Gravitational potential energy Chemical potential energy Sound energy Electrical potential energy Elastic potential energy Nuclear potential energy
State the law of conservation of energy
Energy cannot be created or destroyed, it can only be transferred from one store to another
What are the energy transfers when something falls?
Energy is transferred from the gravitational potential energy store to the kinetic energy store
What are the 3 types of fossil fuel?
Oil
Coal
Natural gas
How was coal formed?
Millions of years ago some trees that died fell into a swamp.
The trees did not rot away because the swamp stopped the bacteria from getting oxygen
Over time mud built up on top of the trees this created a lot of pressure which crushed the trees
Being crushed for millions of years caused the dead trees to turn into coal
How was oil formed?
Millions of years ago sea creatures died and fell onto the seafloor
Over time sand piled up on top of the sea creatures
The weight of all of the sand created a very high pressure which crushed the dead sea creatures
Being crushed turned the sea creatures into oil
What are the 4 non renewable sources of energy?
Coal, oil, natural gas and nuclear
List 7 different types of renewable energy generation
Hydroelectric Solar Geothermal Wind Wave Tidal Biomass
What are the main problems caused by fossil fuel power stations
Acid rain - coal fired power stations produce sulphur dioxide. This gas mixes with water in clouds to make sulphuric acid, which falls as acid rain
Global warming - Fossil fuel power stations produce carbon dioxide. When this gas is in the atmosphere it stops thermal energy from leaving the earth. This means the earth heats up (global warming)
What type of energy store does food store energy in?
Chemical energy store
If something is moving very fast, what energy store does it have a lot of energy in?
Kinetic energy store
If something is very high up, what energy store does it have a lot of energy in?
Gravitational potential energy store
What would you expect to feel if you touched an object with a lot of energy in the thermal energy store?
It is very hot
How would you test some food to see how much energy it contains?
You set it on fire, hold it under a beaker of water and see how much it heats up the water. The more it heats up the water the more chemical energy it had stored up.
Why might someone need to consume more food to take in more energy?
If they are growing, or are very active (a sports person).
Men also need to eat a bit more than women every day
Explain how wind power generators work
What are the energy transfers in the generator?
What are the problems with them?
The wind turns the turbine, the turbine turns a generator which generates the electricity
energy transfer: Kinetic energy (in wind) --> electrical energy (in wires)
The problem is that it only works when the wind is blowing and some people think they look bad
Explain how hydroelectric power stations work
What are the energy transfers in this power station
What are the problems with them?
Water that is in a lake high up is allowed to flow downwards through the power station. This turns a turbine which turns a generator, generating the electricity.
energy transfers:
gravitational potential energy (in high up water) –> kinetic energy (in falling water) –> electrical potential energy (in wires)
The problems are that they cause flooding of local areas which kill wildlife
What are the good and bad points of tidal energy generation
Good points:
Always works as there are always tides
Renewable
Do not cause global warming
Bad points:
Ships cannot sail where the generators are
What are the good and bad points of geothermal energy generation
Good points: It is cheap It can be done locally (for just one house) Renewable Does not cause global warming
Bad points:
It can only be set up where there are hot rocks that can heat the water
What are the good and bad points of solar energy?
Good points:
Can generate energy for just one house (local generation)
Does not take up much space as they can be put on the roof of a house
Renewable
Do not cause global warming
Bad points:
Expensive to install
Does not work as well on a cloudy day
What are the energy transfers in a torch?
Chemical potential energy (in battery) –> electrical potential energy (in wires) –> light energy (in bulb)
What are the energy transfers in an object that is falling?
Gravitational potential energy (when it is high up) –> kinetic energy (moving fast)
What are the good and bad points of wind energy generators?
Good points:
They are renewable
They do not cause global warming
Good to use in windy countries like the UK
Bad points:
They are unreliable because they do not work when there is no wind
Some people think that they look bad and spoil the environment
Explain why people use fossil fuel power stations even though they are bad for the environment.
Fossil fuel power stations are cheap to build and to run.
They are very reliable because they can be used at any time and do not depend on the weather
What are the three types of fossil fuel?
Coal
Oil
Natural gas
What are the energy transfers of a solar panel?
Light energy (from sun) –> electrical potential energy (in wires)
What are the energy transfers in a hairdryer?
electrical potential energy (in wires) –> thermal energy (in heater) and kinetic energy (in the moving fan)
Finish this sentence:
Something stores a lot of gravitational potential energy when it is ____________
High up
Finish this sentence:
Something stores a lot of kinetic energy when it is ____________
Moving fast
Finish this sentence:
Something stores a lot of light energy when it is ____________
Bright
Finish this sentence:
Something stores a lot of elastic potential energy when it is ____________
Stretched
A battery stores energy as _____________
Chemical potential energy
What type of energy do electrons carry around an electric circuit
Electrical potential energy
