Conservation Of Energy

Question 1

What is an energy store?

Answer 1

Energy that an object can have

Question 2

What is an energy transfer?

Answer 2

Energy that only exists when energy is being moved

Question 3

What are the 6 energy stores?

Answer 3

Gravitational Potential
Elastic potential
Thermal
Kinetic
Chemical
Nuclear

Question 4

What are the 5 energy transfers?

Answer 4

Work done
—> by forces
—> against electrical resistance

By radiation
—> sound
—> light
—> heating

Question 5

What happens to wasted energy?

Answer 5

Ends up dissipated into the environment and as a thermal store (air gets slightly warmer)

Question 6

What is the principle of energy conservation?

Answer 6

Energy cannot be created or destroyed, only transferred or stored

Question 7

What is the efficiency equation?

Answer 7

Useful energy out
—————————
Total energy in

Question 8

State an example of energy transfers happening:

Answer 8

1. An object moving up a slope
   Store= kinetic—> transfer= work done—> store= GPE
2. Bringing water to the boil
   Store= n/a —> transfer= heating, electrical—> store= thermal
3. Car braking
   Store= kinetic—> transfer = work done against friction—> store= thermal

Question 9

State the equation for GPE:

Answer 9

GPE= Mass X Gravity X Height

Question 10

State the equation for Kinetic energy:

Answer 10

KE = 1/2 X Mass X Velocity squared

Question 11

What does efficiency mean?

Answer 11

The proportion of useful energy coming out compared to the energy put in

Question 12

What is the unit for GPE/Kinetic energy?

Answer 12

J (joules)

Question 13

What are some ways to keep a house warm?

Answer 13

Cavity walls
Loft insulation
Double glazed windows
Thicker walls
Carpets

Question 14

What does a good insulator do?

Answer 14

Stops conduction, convection and IR radiation

Question 15

What is thermal conductivity?

Answer 15

How easily a certain material loses its heat energy

Question 16

High thermal conductivity=

Answer 16

Material will cool quickly

Question 17

What is an insulator?

Answer 17

A material that keeps its heat

Question 18

What is conduction?

Answer 18

Conduction is how thermal energy travels through solids. In a solid, the particles are tightly packed together in fixed positions. The particles are close together, vibrating in fixed positions. As the solid is heated, thermal energy is transferred into kinetic energy in the particles.

Question 19

What is radiation?

Answer 19

Radiation involves transfer of heat via infra red waves, unlike thermal conduction and convection which need the vibration or movement of particles. This means radiation can occur in a vacuum, where there are no particles of matter. The sun provides heat to the earth due to radiation.

Question 20

What is convection?

Answer 20

Convection occurs when particles with a lot of heat energy in a liquid or gas move and take the place of particles with less heat energy

Question 21

Why is a vacuum good?

Answer 21

Prevents conduction and convection

Question 22

Why is a rubber seal good?

Answer 22

Prevents conduction

Question 23

See book to test on power stations

Question 24

How does kinetic energy work?

Answer 24

Energy in a moving object

Question 25

How does GPE work?

Answer 25

Energy from being high up in a gravitational field

Question 26

How does sound energy work ?

Answer 26

Energy passed through pressure waves

Question 27

How does light energy work ?

Answer 27

Energy detected by our eyes

Question 28

How does thermal energy work?

Answer 28

Energy held in a hot object

Question 29

How does heating work?

Answer 29

Energy moved by conduction, convection or IR radiation

Question 30

How does chemical energy work?

Answer 30

Energy held in the bonds of different molecules

Question 31

How does nuclear energy work?

Answer 31

Energy holding atoms together

Question 32

How does Elastic potential energy work?

Answer 32

Energy in something stretched or compressed

Question 33

How does electrical energy work?

Answer 33

Energy from the movement of electrons

Question 34

State 4 points on the changing use of energy resources in the UK:

Answer 34

1. Coal has decreased to virtually nothing, from being the main source of energy, as it releases CO2 and contributes to global warming 2. Renewable energy has increased as they are renewable and better for the environment 3. Gas is 1/3 of our energy resources 4. Wind and solar is increasing as they are renewable and clean

Question 35

provides cheap power with well-known technology, but produces CO2 (a greenhouse gas) as well other particulates that lead to poor air quality?

Answer 35

Coal

Question 36

Is expensive is to build and has ecological impact, but is renewable and reliable?

Answer 36

Tidal Hydroelectric

Question 37

Is renewable and relatively cheap, but isn’t reliable and people don’t like the look of them on the whole?

Answer 37

Wind

Question 38

Is not renewable, but is unlikely to run out any time soon; however, it has very bad PR and is incredibly expensive? It also does not release CO2, which is good…

Answer 38

Nuclear

Question 39

Is renewable, can be put anywhere including on micro scale (ie not whole power stations), but is unreliable and takes up lots of space if you want a decent output?

Answer 39

Solar

Question 40

Is of interest to the UK in terms of a connection to Iceland, but we can’t build them ourselves? Renewable, reliable…

Answer 40

Geothermal

Question 41

Is widely used in the UK, as we have our own fuel source, and also has a quick start-up time so we can get them online when everyone turns their kettles on, BUT are non-renewable, getting more expensive?

Answer 41

Gas

Question 42

Is renewable, and can be built to STORE ENERGY by using pumps when there’s not much demand…

Answer 42

Hydroelectric

Question 43

Is renewable, but very expensive, and requires very specific locations, but is reliable too…

Answer 43

Tidal

Question 44

Is renewable, and is CARBON NEUTRAL, but does release CO2, and fuel supply is a problem if you’re thinking of scaling up?

Answer 44

Biomass

Question 45

State 2 ways that coal is harmful to the environment:

Answer 45

1. Release CO2 —> global warming 2. Creates smog—> Respiratory problems

Question 46

State what happens to the wasted energy:

Answer 46

Dissipated to the surroundings

Question 47

In what way does the thickness of a material affect how good an insulator it is?

Answer 47

Air gets trapped

Question 48

Are fossil fuels renewable ?

Answer 48

No

Question 49

Are nuclear power stations renewable?

Answer 49

No

Question 50

Are biomass power stations renewable?

Answer 50

Yes

Question 51

Are wind power stations renewable?

Answer 51

Yes

Question 52

Are wave power stations renewable?

Answer 52

Yes

Question 53

Are tidal power stations renewable?

Answer 53

Yes

Question 54

Are hydroelectric power stations renewable?

Answer 54

Yes

Question 55

Are geothermal power stations renewable?

Answer 55

Yes

Question 56

Are solar power stations renewable?

Answer 56

Yes