Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Core Physics > P1.4 - Methods we use to generate electricity > Flashcards

P1.4 - Methods we use to generate electricity Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What are the non-renewable energy resources?

A

Coal

Oil

Natural gas

Nuclear fuels (uranium and plutonium)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the characteristics of non-renewable energy resources?

A

They will all run out one day and they cause environmental damage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why are gas and oil power stations used to provide electricity at peak times?

A

Gas and oil-fired stations provide electricity at peak times as they have short start up times, while nuclear and coal power stations provide the main supply of electricity because of their large start up times.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the start-up time order?

A

Gas
Oil
Coal
Nuclear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the renewable energy resources?

A

Wind

Waves

Tidal

Hydroelectric

Solar

Geothermal

Food

Biofuels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What characteristics of renewable energy resources are there?

A

They will never run out, however they do not provide as much energy as non-renewable resources as many depend on the weather.

They also damage the environment, albeit not as much as non-renewable resources do.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the process for generating electricity in a typical power station?

A

The fossil fuel is burned to convert its stored chemical energy into heat energy.

The heat is used to heat water or air to produce steam.

The steam turns a turbine, converting heat energy into kinetic energy.

This turbine is connected to a generator, which transfers kinetic energy into electrical energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the advantages of fossil fuels?

A

They are relatively cheap.

They are ready-made and able to be used whenever.

They generate a lot of electricity when burned.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the disadvantages of fossil fuels?

A

They are non-renewable.

They release carbon dioxide when they are burned, contributing to global warming.

Burning coal and oil releases sulfur dioxide, causing acid rain. This may harm trees and living things.

They have to be near their suppliers - coal in a coal mine, etc.

Coal mining can disfigure the landscape.

Oil spillages may occur, harming the aquatic animals.

Visual and noise pollution when burned.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How do nuclear power stations work?

A

They work like regular power stations but instead use the nuclear fission of uranium or plutonium to release lots of energy.

The heat produced makes steam, which drives the turbine and eventually the generator is powered.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the advantages of nuclear power stations?

A

The process does not produce carbon dioxide or sulfur dioxide.

A small amount of radioactive material will release a lot of energy.

The fuel is cheap.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the disadvantages of nuclear power stations?

A

The nuclear waste is dangerous and difficult to dispose of.

There is a risk of a catastrophe like the Chernobyl disaster of 1986.

Nuclear power stations cost a lot and need engineering to make them safe.

They have a long decommissioning period.

They take the longest to start-up.

They use non-renewable resources.

Visual and noise pollution.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where are wind turbines placed?

A

Wind turbines are placed in areas where wind will reach them.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do wind turbines work?

A

The wind directly turns the blades, which turn the generator.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the advantages of wind power?

A

Wind is entirely renewable.

No harmful gases are produced.

They only take up a small space, so the area below the turbine can be used.

Remote areas that are not connected to the grid can use wind turbines to produce their own supply of electricity.

There are no fuel costs and minimal running costs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the disadvantages of wind power?

A

They only work when wind is present. You cannot increase the supply when there is more demand.

The initial costs are rather high.

There is both visual and noise pollution.

Birds could die if they get trapped in the blades, thus affecting the local ecosystem.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How do solar cells work?

A

Solar cells generate currents directly from sunlght.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where are solar cells used?

A

They are often used in remote places with little access to the mains supply, such as on roads for signs or in third-world countries.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why do solar cells usually not exist on the National Grid?

A

They generate electricity on a small scale, so it is not practical to connect them to the National Grid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the advantages of solar cells?

A

The Sun’s rays are renewable.

There is no pollution.

They are only reliable in times where there is a lot of sunlight, so third-world countries benefit from this.

The energy is free.

They are effective and versatile in generating electricity on a short scale.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the disadvantages of solar cells?

A

Making the cells themselves leads to pollution.

Initial costs are high.

They are only reliable in times where there is a lot of sunlight.

They are only useful for small-scale purposes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How does hydroelectric power work?

A

Water is collected in a reservoir, which can then flow downhill and turn turbines at the bottom of the hill.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe the energy transfers in a hydroelectric power station.

A

Water moves from a higher level to a lower level, thus transferring gravitational potential energy to kinetic energy. The turbine is turned by the water to then power a generator. This transfers kinetic energy to electrical energy.

24
Q

What are the advantages of hydroelectric power?

A

It is renewable.

The water can be re-used to make more electricity.

There are no fuel costs and running costs are minimal.

It is useful in remote areas on a small scale.

It can provide an instant response to an increased demand.

25
Q

What are the disadvantages of hydroelectric power?

A

If there is a drought then there is an issue.

The ecosystem may be disrupted.

There is visual and noise pollution.

The water supply to the local population would be affected.

The flooding of the valley leads to rotting vegetation and the release of methane and carbon dioxide.

26
Q

How does wave power work?

A

As waves come to the shore, they move up and down and push air upwards in the direction of a turbine and generator via kinetic energy.

27
Q

What are the advantages of wave power?

A

Waves are renewable.

There is no pollution.

There are no fuel costs and running costs are minimal.

This is very useful on small islands.

28
Q

What are the disadvantages of wave power?

A

There is visual pollution.

They are hazards to boats.

Initial costs are high.

They are unreliable - they depend on the waves.

29
Q

What are tidal barrages?

A

Tidal barrages are big dams over river estuaries with turbines in them. The source of energy is the gravity of the Sun and the gravity of the Moon.

30
Q

How does tidal power work?

A

As the tide comes in, it fills up the estuary and drives the turbines. The water can be allowed out through the turbines at a controlled speed.

31
Q

What are the advantages of tidal power?

A

Renewable and reliable - the tide is twice a day.

There is no pollution.

There are no fuel costs and running costs are minimal.

They can double as bridges.

They can store energy in times of high demand.

32
Q

What are the disadvantages of tidal power?

A

Expensive to make.

There are very few suitable places due to the lack of tidal areas.

The tide can vary so the energy cannot be fully predicted.

Boats may be affected.

There is visual pollution.

33
Q

Where is geothermal energy useful?

A

Geothermal energy is useful in volcanic areas, such as Iceland.

34
Q

How does geothermal energy work?

A

The slow decay of various radioactive elements, including uranium, is the source of the heat.

The steam and hot water rise to the surface and drive a turbine and generator.

35
Q

What are the advantages of geothermal?

A

The geothermal heat can also be used to heat local homes.

It is renewable.

Carbon dioxide is not produced.

There are no fuel costs.

36
Q

What are the disadvantages of geothermal?

A

It can only be used in certain areas.

Dangerous elements found may be a concern.

The volcanic activity may stop - the power station is redundant then.

37
Q

How do biofuels generate electricity?

A

Biofuels can generate electricity in the same way as fossil fuels.

They are burnt to heat water.

38
Q

Name some examples of biofuels (electricity).

A

Solids - straws, woodchips

Liquids - ethanol

Gases - methane

They are from organic matter.

39
Q

What are the advantages of biofuels in generating electricity?

A

They are renewable.

They are reliable.

They are supposedly carbon neutral because the carbon dioxide absorbed during photosynthesis is released

40
Q

What are the disadvantages of biofuels in generating electricity?

A

The land used for growing biofuels disrupts the ecosystem and potential crops.

Carbon dioxide is released with the transport of these materials.

The burning and decay of forests cleared for biofuels releases carbon dioxide and methane.

41
Q

What is carbon capture and storage’s purpose?

A

Carbon capture and storage aims to reduce the levels of carbon dioxide in the atmosphere and reduce the intensity of the greenhouse effect.

42
Q

How does carbon capture and storage work?

A

It collects carbon dioxide from the power stations and pumps it into empty gas or oil fields like those under the North Sea. It is an emerging and developing technology.

43
Q

What is the National Grid?

A

The National Grid is the network of transformers and cables that takes electricity from power stations anywhere on the grid and supplies it to anywhere else on the grid.

44
Q

What is needed to transmit electrical power via the National Grid?

A

A high voltage is needed.

A high current means more energy is lost through heat in the cables.

45
Q

How do transformers affect transmission?

A

To get the voltage to 400,000, the transformers step up the voltage at one end with the step-up transformer and bring it down to a safe, domestic level with a step-down transformer.

46
Q

What is the main purpose of transformers?

A

They increase and decrease the voltage to minimise the current and power loss.

47
Q

What are the advantages of overhead cables?

A

They have a low set up cost.

Faults are easy to access.

They are easy to set up.

There is minimal disturbance to land.

48
Q

What are the disadvantages of overhead cables?

A

Lots of maintenance is needed.

They look ugly.

They are affected by the weather.

They are not fully reliable.

49
Q

What are the advantages of underground cables?

A

They require minimal maintenance.

They are hidden.

They are not affected by the weather.

They are more reliable.

50
Q

What are the disadvantages of underground cables?

A

There is a higher setup cost.

They are hard to access.

They are hard to set up.

There is a lot of disturbance to the land.

51
Q

How must the Grid meet our energy demands?

A

In order for the National Gird to meet our demands, the energy supplied must increase or our demands must be reduced.

52
Q

How can demand be reduced?

A

Demand can be reduced by using more energy efficient appliances and using less electricity.

53
Q

How can the supply be increased?

A

The supply can be increased by opening more power stations or increasing the power output.

54
Q

When does demand for electricity commonly fall?

A

There is often a surplus of electricity at night when demand falls but electricity is still being generated.

55
Q

How does pumped storage work?

A

To store surplus energy for later use, water flows from to a top reservoir to be stored from a bottom one via “stored” electricity.

In times of high demand, the water is released into the bottom reservoir and powers a generator, which provides electricity.

The water is pumped back up in low-demand times.

56
Q

What are the advantages of pumped storage?

A

This is renewable.

There is no pollution.

It is reliable.

it is a free energy resource.

57
Q

What are the disadvantages of pumped storage?

A

It only works in hilly areas.

It can cause floods if one reservoir leaks.

Wildlife, etc, is damaged.

Core Physics (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions