energy

Question 1

energy stores

Answer 1

kinetic energy store, gravitational potential energy store, elastic potential energy store, electrostatic energy store, magnetic energy store, chemical potential energy store, nuclear energy store, thermal energy store

Question 2

kinetic energy

Answer 2

the energy of a moving object

Question 3

gravitational potential energy

Answer 3

the energy something gains when you lift it up, and which it loses when it falls

Question 4

elastic potential energy

Answer 4

the energy of a stretched spring or elastic band

Question 5

electrostatic energy

Answer 5

the energy due to the force of attraction (or repulsion) between two charges

Question 6

magnetic energy

Answer 6

the energy due to the force of attraction (or repulsion) between two magnets

Question 7

chemical potential energy

Answer 7

the energy contained in a chemical substance

Question 8

nuclear energy

Answer 8

the energy contained within the nucleus of an atom

Question 9

thermal energy

Answer 9

the energy something has due to its temperature (or state)

Question 10

energy transfers

Answer 10

mechanically, electrically, heating, radiation

Question 11

mechanically (energy transfer)

Answer 11

when a force acts on a body, energy can be transferred between two stores

Question 12

electrically (energy transfer)

Answer 12

electricity can transfer energy from a power source, delivering it to components within a circuit

Question 13

heating (energy transfer)

Answer 13

thermal energy can be transferred from place to place by the process of conduction, convection and thermal radiation

Question 14

law of conservation of energy

Answer 14

energy is not created or destroyed, it can only be used or transferred from one store to another

Question 15

efficiency formula

Answer 15

useful energy output/ total energy output x100

Question 16

gravitational potential energy formula

Answer 16

mass x gravitational field strength x height

Question 17

relationship between work done and energy transferred

Answer 17

work done=energy transferred

Question 18

work done formula

Answer 18

work done=force x distance

Question 19

what is power

Answer 19

power is the rate at which energy is transferred or the rate at which work is done

Question 20

power formula

Answer 20

power= work/time

Question 21

kinetic energy formula

Answer 21

ke= 1/2 x mass x velocity2

Question 22

thermal conduction

Answer 22

the transfer of thermal energy through a substance by the vibration of the atoms within the substance

Question 23

convection

Answer 23

the transfer of heat through fluids by the upward movement of warmer, less dense regions of fluid

Question 24

radiation

Answer 24

the transfer of energy by infrared waves

Question 25

GPE

Answer 25

the GPE of an object will increase if we apply a force on it in the opposite direction to the pull of gravity

Question 26

non-renewable resources of energy

Answer 26

• burning fossil fuels
• nuclear fuel

Question 27

fossil fuels +-

Answer 27

+cheap
+ can generate large amount of electricity in a single location

• produces sulphur dioxide which causes acid rain
• non-renewable, cannot be replaced easily
• adds CO2 to the atmosphere

Question 28

nuclear fuel +-

Answer 28

+ ‘clean’ it does not produce greenhouse gases

• nuclear power stations are expensive to build
• non-renewable
• accidents and problems with disposal of radioactive material

Question 29

electricity generated in power stations

Answer 29

heat from nuclear fuel or burning fossil fuels is used to heat water. high-pressure steam is produced that makes the blades of a turbine spin. turbine is used to turn the generator (this generates the electricity)

Question 30

renewable energy resources

Answer 30

• hydroelectric power
• wave energy
• wind power
• solar power

Question 31

hydroelectric power

Answer 31

hydroelectric pjower station uses a turbine to turn the generators. these power stations use the stored GPE of water in high reservoirs built in the mountains, the GPE is transferred to KE as the water flows down the mountain to the power station below

Question 32

hydroelectric power +-

Answer 32

+ clean
+ renewable

• building the reservoirs and power stations can spoil the landscape
• reservoir can destroy the natural habitat for wildlife

Question 33

tidal power

Answer 33

generate power by turning turbines as the tide flows into a dammed river estuary- where a river joins the sea.

Question 34

tidal power +-

Answer 34

+ renewable
+ more powerful than wind since water is denser
+ clean source of energy does not release greenhouse gases

• expensive
• dams might damage habitats for wildlife

Question 35

wave energy

Answer 35

energy can be extracted from waves, the continuous movement of the surface of the sea and oceans is the result of a combination of tides and wind

Question 36

wave energy +-

Answer 36

+ clean, produces no greenhouse gases

• Wave-powered generators do not work in calm water
• Wave-powered generators do not produce very much electricity

Question 37

wind power +-

Answer 37

+ clean
+ land under wind turbines can still be used for farming
+ renewable

• lots of wind turbines are needed to produce useful amounts of electricity
• can cause noise pollution and may kill birds and bats

Question 38

solar power

Answer 38

photovoltaic cells transfer light energy directly to electrical energy

Question 39

solar power +-

Answer 39

+ renewable
+ don’t produce greenhouse gases

• only work when it is sunny
• expensive
• only 15% efficient

Question 40

geothermal energy +-

Answer 40

+ renewable
+ does not produce pollution

• expensive