1. Energy (efficiency, national and global energy resources)

Question 1

What is efficiency?

Answer 1

Efficiency is the ratio of the useful work done by a machine, engine, device, etc, to the energy supplied to it, often expressed as a percentage

Question 2

What is the equation for efficiency?

Answer 2

useful power output
____________________________
total power input

Question 3

How can the efficiency of a system be increased?

Answer 3

• Reducing waste output (lubrication, thermal insulation)
• Recycling waste output

Question 4

What is an example of recycling waste output?

Answer 4

Absorbing thermal waste and recycling as input energy

Question 5

What are the main energy resources for use on earth? (9)

Answer 5

• Fossil fuels (coal, oil, gas)
• Nuclear fuel
• Biofuel
• Wind
• Hydro-electricity
• Geothermal
• Tidal
• Solar
• Water waves

Question 6

What are examples of non-renewable energy resources?

Answer 6

• Coal
• Oil
• Gas
• Nuclear fuel

Question 7

What are examples of renewable energy resources? (7)

Answer 7

• Biofuel
• Wind
• Hydro-electricity
• Geothermal
• Tidal
• Solar
• Water waves

Question 8

What are renewable energy resources?

Answer 8

Energy resources that are being replenished as it is used

Question 9

What are non-renewable energy resources?

Answer 9

Energy resources that are finite

Question 10

What are energy resources used for?

Answer 10

• Transport
• Electricity generation
• Heating

Question 11

What are the advantages of renewable energy?

Answer 11

• It is being replenished as it is being used, so it will never run out
• It does not contribute to global warming
• They can do damage to the environment, but a lot less than non-renewable resources do

Question 12

What are the disadvantages of renewable energy resources?

Answer 12

• They are very expensive
• They don’t provide much energy
• Some of them are unreliable because they are dependent on the weather

Question 13

What are the disadvantages of fossil fuels?

Answer 13

• They will run out one day
• They release greenhouse gases: carbon dioxide and sulfur dioxide

Question 14

What are the advantages of fossil fuels?

Answer 14

• They provide a large amount of energy, so can be used for more large-scale energy supplies
• They are reliable
• they are abundant
• they are relatively cheap

Question 15

What are fossil fuels and how are they formed?

Answer 15

They are natural resources that form underground over millions of years

Question 16

How is nuclear energy generated?

Answer 16

• Nuclear fuels are reacted to heat water to produce steam
• the steam turns turbines to generate electricity

Question 17

How is energy from biofuels generated?

Answer 17

fromthe burning of plant-matter, methane or ethanol

Question 18

How is energy from hydroelectricity generated?

Answer 18

Water is stored at a height, and when released, rushing water turns turbines directly to generate electricity

Question 19

How is tidal energy generated?

Answer 19

The movement of water due to tides turn turbines directly to generate electricity

Question 20

How is geothermal energy generated?

Answer 20

• Hot rocks underground are used to heat water to produce steam
• the steam is used to turn turbines which generate electricity

Question 21

How are water waves used to generate electricity?

Answer 21

Moving water due to waves turn turbines directly to generate electricity

Question 22

How do solar cells generate electricity?

Answer 22

They generate electric currents directly from sunlight

Question 23

What energy resources are used for transport fuel for vehicles?

Answer 23

• Fossil fuels (coal and oil)
• Biofuels
• Renewable energy resources (electric cars)

Question 24

What can renewable and non-renewable energy stations involve destroying?

Answer 24

Landscapes and habitats

Question 25

What are energy resources?

Answer 25

large stores of energy that can be used to generate electricity and heat homes and businesses

Question 26

What energy resources can be used for heating?

Answer 26

• Coal
• Natural gas
• Geothermal heat pump
• Solar water heaters
• Biofuel

Question 27

What are the environmental impacts of renewable and non-renewable energy resources based on the extraction of energy?

Answer 27

• Fossil fuels involve destroying landscapes
• Wind turbines can be considered an eyesore

Question 28

What are the environmental impacts of renewable and non-renewable energy resources based on the use of them?

Answer 28

• Fossil fuels release greenhouse gasses, like carbon dioxide and sulfur dioxide.
• Carbon dioxide contributes to global warming
• Sulfur dioxide causes acid rain
• Solar and wind directly create electricity with no emissions

Question 29

What are the patterns and trends of energy use?

Answer 29

• During the industrial revolution, fossil fuels became an important source of energy as it was easy to mine, and provided a lot of energy
• Only recently has renewable energy become more suitable - technology has had to develop a lot since the industrial revolution to be able to harness such energy sources efficiently.
• It is easier to use energy resources due to increasing pressure to cope with the public’s increasing power demands but harder to solve environmental issues due to political, social, ethical and economic considerations.

Question 30

How does a coal power station work?