Physics 1b Flashcards
What are the four types of non-renewable energy resources ?
Coal
Natural gas
Oil
Nuclear
What are the renewable energy sources ?
Wind Wave Tidal Hydroelectric Solar Geothermal Biofuels
How does oil generate electricity ?
- Fossil fuel burnt, converting chemical energy to heat.
- This heats water and turns it into steam
- The steam turns a turbine, converting heat to kinetic energy
- A generator converts the kinetic energy to electrical energy
What are the disadvantages of wind power ?
Some consider them an eyesore
Sound pollution
No power when the wind stops so unreliable
How do wind turbines work ?
A generator converts the kinetic energy of the wind blowing the blades into electrical energy
What are the disadvantages of hydroelectric power ?
- Valleys flooded which damage environments
- People are moved out of their homes to make way for the dams
- High initial costs
What is a new way hydroelectric dams work when it’s not raining so much ?
There is a second ‘lower reservoir’ and a pump which keeps the higher reservoir full
How do tidal barrages work ?
They are basically bridges built across an estuary that has turbines inside them, generators convert the kinetic energy to electrical energy
True or false- biofuels work in the same way as crude oil does
True - they heat steam which turns a turbine
What is geothermal energy ?
Water is pumped down deep under ground where the heat from the rocks turns the water to steam when it comes back up. Then the steam turns a turbine and then that turns a generator.
What is a major drawback of geothermal power ?
You need to be in very specific locations and it is very expensive
Other than burning fossil fuels, how are non renewable energy sources bad for the environment ?
- Coal mining makes a mess
- oil spillages damage sea wildlife
- nuclear waste is extremely dangerous
- nuclear disasters like Chernobyl
- burning any fuel gives off CO2 (causes global warming) and SO2 (causes acid rain)
True or False - non renewable set up cost are higher than renewable
Why ?
False - renewable energy sources need bigger power stations therefore cost more
What is carbon capture ?
Carbon capture is when you collect the CO2 before it is released into the atmosphere. It is then pumped into empty oil fields (caves underground) and therefore doesn’t contribute to the greenhouse effect
Who distributes electricity to the country ?
National grid
What do step up transformers do ?
Increase the voltage so that it can be distributed across the UK - this reduces the current so there is very little power lost due to heating the wires.
What do step down transformers do ?
Bring down the voltage to safe usable levels
Why are some cables now put under ground ?
It is more reliable / unaffected by weather / minimal maintenance / hidden away
What is the amplitude of a wave ?
Height from rest position
What is wave length ?
The length of a full cycle
What is the frequency ?
The amount of complete waves passing a certain point in a second