prior knowledge: multichoice questions · web viewthe total chemical energy store decreases. in...

Name: ______________________________Class: ____________________

Year 8 Topic 2a: Energy (Physics)

Contents Contents........................................................................................................................................................... 2

Prior knowledge: MultiChoice Questions ....................................................................................................3Introduction to energy..................................................................................................................................... 4

Misconceptions about energy......................................................................................................................48 Energy Stores.............................................................................................................................................54 Energy Pathways....................................................................................................................................... 6

More about the 8 Energy Stores......................................................................................................................7

Kinetic energy store ................................................................................................................................ 7Investigating kinetic energy: Speed..........................................................................................................8

How we gain agreement that an idea is correct in science........................................................................11Gravitational potential energy store..........................................................................................................12

Investigating gravitational potential energy store..................................................................................13Chemical store............................................................................................................................................15

Comparing chemical energy store in different exothermic reactions.....................................................15Thermal store............................................................................................................................................. 16

Investigating relationship between thermal store and temperature......................................................16Elastic store................................................................................................................................................ 17

Investigating the elastic energy store of strawberry laces......................................................................17Energy transfers along pathways...................................................................................................................19

Misconception with Work Done.................................................................................................................21Mechanical Work Done Pathway...............................................................................................................21Radiation pathway......................................................................................................................................22Heat Pathway............................................................................................................................................. 22Electrical Work Done Pathway...................................................................................................................23Dissipation of energy and efficiency...........................................................................................................23Modelling energy transfers........................................................................................................................ 25Energy transfer circus.................................................................................................................................28Investigate a factor that affects how high a ball bounces..........................................................................30

Power............................................................................................................................................................. 34Generating electricity and energy resources.................................................................................................35

Sustainability, climate change and the greenhouse effect.........................................................................35Non-renewable sources..............................................................................................................................36

Fossil fuels...............................................................................................................................................36Nuclear fuel............................................................................................................................................ 39

Renewable sources.....................................................................................................................................41Biofuels................................................................................................................................................... 41Wind and wave power............................................................................................................................42Tidal power and hydro-electricity...........................................................................................................43Solar power.............................................................................................................................................44Geothermal power..................................................................................................................................45

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Knowledge Organiser Questions ...............................................................................................................47

Prior knowledge: MultiChoice Questions 1. What are the units of energy?

a) Watts b) Joules c) Degrees centigrade

d) Newtons e) Metres/Second

2. How many energy stores are there?a) 8 b) 9 c) 10 d) 11 e) 12

3. Which is not an energy store?a) Solar b) Chemical c) Nuclear d) Thermal e) Kinetic

4. How many energy pathways are there?a) 2 b) 4 c) 6 d) 8 e) 10

5. Which is not an energy pathway?a) Mechanical work

doneb) Electrical work

donec) Heatin

gd) Kinet

ice) Radiati

on6. What type of pathway generates heat by friction?

a) Mechanical work done

a) Electrical work done

b) Heating

c) Kinetic

d) Radiation

7. Everything in the Universe is either mass or what?a) Particles b) Stars c) Weight d) Energy e) Space

8. What does renewable mean?a) Can use

it againb) Will not

run outc) Does not

release carbon dioxide

d) Will burn for a long time

e) Used quicker than it is made

9. Over what time period are fossil fuels made?a) Days b) Years c) Hundreds of

yearsd) Thousands of

yearse) Millions of

years10. Which two are not fossil fuels?

a) Coal b) Bio-fuel c) Nuclear d) Gas e) Oil11. Other than the fossil fuels name one more non-renewable fuel.

a) Geothermal b) Bio-fuel c) Nuclear d) Hydroelectric

e) Batteries

12. Which fuel is not burnt to use its energy store?a) Coal b) Bio-fuel c) Nuclear d) Gas e) Oil

13. What pollutant is released when we burn fuels?a) Global

warmingb) CO2 c) CO2 d) Co2 e) CO2

14. Which energy resource uses the chemical energy store in material from recently living organisms?a) Crude Oil b) Bio-fuel c) Hydroelectr

icd) Natural gas e) Horsepower

15. Which is the correct mnemonic for the energy stores and energy transfers?a) b) MRS

GREc) Richard of York

Gave Battle in d) Rich Men in

Vegas Use X-e) CUB

SURCARf) 8 kg

cement for

3

N Vain ray Glasses Mr HeReflection – Before the topic Reflection - End of the topicWhat were you pleased with? Score: / 15

What were you pleased with?

Introduction to energy Everything in the Universe can be sorted into one of two groups: Matter (objects with mass) and Energy. Energy is the capacity of something to do work. Either it is doing something, or it has the potential to do something.

James Prescott Joule, (1818-1889) was the son of a brewer. He spent much of his time experimenting with electricity, engines and heat. It was he who identified that forms of energy—mechanical, electrical, and heat—are basically the same and can be changed one into another. He formed the basis of the law of conservation of energy, the first law of thermodynamics. In recognition of his work, the units of energy are named Joules or J in his honour.The law of conservation of energy states that energy cannot be created or destroyed. It is only moved from one store to another.

16. What is the Law of Conservation of Energy?17. Is it possible to make new energy?18. What is the unit of energy? What are the two ways we can write

it?19. What two things can everything in the Universe be sorted into?20. What does conserve mean?Misconceptions about energy

The big idea of this topic is that energy is never lost.There are many misconceptions in this topic and most stem from differences between the everyday and scientific use of the term ‘energy’. We must be careful that we remember that energy is never used up and can only exist in one of the 8 stores or 4 pathways described next in this booklet.Here are some scientifically incorrect uses of the term energy: I’m tired because I have run out of energy or I can run very fast because I have a lot of energy. Exercise is good for you because it builds up your energy, when we run out of energy we need medicines and vitamins.

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Some objects contain a lot of energy that can be consumed and then used up to help us move about and to make other things happen.These should read something like this: I am tired because I have transferred energy from the chemical store of my food to other stores such as kinetic or thermal. I can run fast when I have a large chemical energy store available. Exercise is good for you as it improves your ability to usefully transfer energy from the chemical store in our bodies. Some objects have a larger energy store than others. This means they have more to transfer.

21. What is wrong with each of these statements?a) When I lift a box onto a shelf I run out

of food energyb) As a car accelerates the energy in its

battery is used up to make it move.c) If a cup of tea cools down it loses

energy to the surroundingsd) A bike gets rid of its energy as it slows

down.8 Energy Stores

There are only 8 ways that energy can be stored. These are known as energy stores. We can remember them using the mnemonic: 8 kg cement. Energy is transferred between them when anything happens.

8Stores

kg

kinetic storegravitational potential store

cement

chemical store elastic potential storemagnetic storeelectrostatic storenuclear storethermal store

22. Draw a line connecting the object with its main store of energy and the reason you think this.

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Object(s) Store of energy Reason

Car

an elastic store it is moving

Burger

a gravitational

store it has chemicals that can react

Book

a kinetic store it is high up

Balloon

a chemical store it is warmer

than the coldest thing

Magnets

a heat store it is squashed and springy

Iron

an electromagnetic

store the magnets will

spring apart

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23. Identify the energy store in each case:a) A book on a shelf b) A catapult pulled back ready to firec) An arrow traveling through the air d) A battery e) Some wood about to go on the fire f) A paperclip being pulled by a magnet g) A hot kettle h) The Suni) A mars bar you are about to eat j) Your wool jumper crackling when you

take it off4 Energy Pathways

Remember that: The law of conservation of energy states that energy cannot be created or destroyed. It is only moved from one store to another.Energy can move between the 8 energy stores using pathways. There are only 4 energy pathways. We can remember them using the mnemonic 4 Mr He. We cannot store energy in pathways.

4 Mr He

Mr

Mechanical work done – moving a forceradiation (light, sound, infra-red)

He

Heat (via conduction through contact)electrical work done (current)

24. Which energy pathway is being used in each case?a) A balloon popping b) Someone pushing a carc) Friction slowing a rolling ball d) When you plug your phone in to

chargee) The water in a saucepan getting

hotter f) Ice melting in your hand

g) A torch shining on the floor h) Toast cooking in a toasteri) You running up a hill j) A cup of tea cooling on a winter day

25. What is the mnemonic we use to remember the energy stores?26. What are the different energy stores?27. What is the mnemonic we use to remember the energy pathways?28. What are the different energy pathways?29. Which of these are energy stores, energy pathways or neither?a) Sound energy store b) Solar energy pathwayc) Battery energy store d) Chemical energy storee) Hot water energy store f) Food energyg) Kinetic energy store h) Nuclear energy storei) Force energy j) Acceleration energy store

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More about the 8 Energy Stores There are only 8 ways that energy can be stored. These are known as energy stores. We can remember them using the mnemonic: 8 kg cement. Energy is transferred between them when anything happens.

8Stores

kg

kinetic storegravitational potential store

cement

chemical store elastic potential storemagnetic storeelectrostatic storenuclear storethermal store

Kinetic energy store All moving things have a kinetic energy store, even very large things like planets, and very small ones like atoms. The size of the kinetic energy store depends upon:- the mass of the object (measured in kg)- the speed of the object (measured in m/s)As an object moves through in gas (e.g. air) or liquid (e.g water) it hits particles. This causes mechanical work done to be transferred via the friction force. In this case energy will be moved to the thermal store of the object and the surroundings. This is why meteorites get hot as they fall through our atmosphere.

30. Which of these objects have a kinetic energy store? A rocket heading through space

An aeroplane sitting on the runway

A particle in a solid vibrating slowly

A particle in a gas

The wind blowing A beam of light31. Can an object have kinetic energy if it is in a vacuum like space? Explain why

you think this?

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Investigating kinetic energy: Speed

Speed of vehicle

How far block is pushed (cm)Test 1 Test 2 Test 3 Mean

Slow

Medium

Fast

Speed of vehicle in this investigation is categoric – that means it does not use numbers. When we plot categoric variables we must use a bar chart.

Use the following structure strip to plan your investigation.

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32. Hypothesis being tested? (simple statement stating a relationship)

34. Independent variable (you change)

35. Dependent variable (you will measure)

36. 3 control variables (ensures only the IV affects the DV – makes it fair)Do not pick same measuring device (ruler)

1)

2)

3)

42. Step by step method (start each line with a command verb e.g. measure, set-up, record)

1)

2)

3)

4)

5)

6)

54. Risk assessment(3 most obvious hazards in your

1)

2)

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experiment and how you will reduce their risk)

3)

Now test your hypothesis using the method. Write your results in the table on page 8.60. Are there any anomalous results (ones that do not fit the pattern)? How can you

tell? If you have some put a circle around them.61. What sort of errors cause anomalous results? Tick the correct box

Random errors – ones we cannot predict Systematic errors – ones we can predict

62. What should we do with anomalous results?63. Calculate the mean average value for the distance the block is pushed for each

speed of car Be careful to round your answer to 1dp using mean = (1st test + 2nd test + 3rd test) ÷ 3 Remember to ignore anomalies e.g. If 2nd test result is anomalous then mean = (1st

test + 3rd test) ÷ 264. Plot a bar chart of Speed of car vs Distance the block is pushed (cm) It should

look something like this when complete

65. Write your conclusion for your chart using this prompt:

As ‘speed’ increases the distance the block is pushed { increasesdecreases

stays the same}. 66. Use your conclusion to describe what must happen to the kinetic store of the car

as it gets faster. Again, write your conclusion for your graph using this prompt:

As ‘speed’ increases the kinetic energy { increasesdecreases

stays the same}. 67. Fill in the blanks in the statement below to describe how your experiment tells

us about the kinetic store of the car.The ___________ the kinetic store of the car as it hits the block, the more energy can be transferred along the _____________ ___________ ___________

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pathway. This means that more work is done against the _______ force and the block must move further. Eventually all the energy is transferred into the _______ store of the surroundings.

68. Does your investigation support your hypothesis? How can you tell?

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How we gain agreement that an idea is correct in science We share our results and methods so that other people can check our claims and ensure they are valid. We call this process peer review. There are three main things we look for to gain confidence that something is correct:1. How reliable is the source? Some are bias or

misleading2. Has the person repeated and got same results? If so,

the results are called repeatable.3. Have different people get similar results using different

methods? If so, we call the results reproducible.Results that have not passed these three checks may be incorrect.

69. What could you do now to increase your confidence that everyone agrees with your answer? What would you hope to find discover?

70. If other people in your class got the same results as you using a different technique (e.g. different slope) would that make your results repeatable or reproducible? Say why?

71. How could you adjust your plan to investigate how mass affects kinetic store of the car?

Use the structure strip on the previous pages to plan that investigation and then carry it out.72. Look at the table in the earlier investigations. Draw a similar table that is

appropriate for this investigation. Remember units.73. Are there any anomalous results (ones that do not fit the pattern)? How can you

tell? If you have some put a circle around them.74. What sort of errors cause anomalous results? Tick the correct box

Random errors – ones we cannot predict Systematic errors – ones we can predict

75. What should we do with anomalous results?76. Calculate the mean average value for the distance the block is pushed for each


test + 3rd test) ÷ 277. Plot a line graph of Mass of car (g) vs Distance the block is pushed (cm).78. Draw your line or curve of best fit. Remember it doesn’t have to touch any of

the points at all.

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79. Write your conclusion for your graph using this prompt:

As ‘mass of car’ increases the distance the block is pushed { increasesdecreases

stays the same}. The steepness of the graph { increases

decreasesstays the same} so the rate of change also { increases

decreasesstays the same} .

80. Use your conclusion to describe what must happen to the kinetic store of the car as it gets heavier. Again, write your conclusion for your graph using this prompt:

As ‘mass’ increases the kinetic energy { increasesdecreases

stays the same}.81. Complete MultiChoice Questions Topic 7.1a. List 5Qs you are happy with and

5Qs you are not.Gravitational potential energy store

When an object is moved higher, its gravitational potential energy store increases. It depends on: the mass of the object the height it gains the gravitational field strength – known as g. On Earth g= 9.8N/kgA falling object moves energy from its gravitational potential store to its kinetic store.

Because the Moon has much less mass than Earth, its gravitational field strength is much less than Earth. Gravity on Moon is only 1.67 N/kg. Gravity on Earth is 9.8N/Kg. This means you weigh less on the Moon. It also means that objects gain less gravitational potential store when lifted.

82. Can an object have gravitation potential energy store in space? Say why you think this?

83. Why are objects easier to lift on the Moon than on the Earth?84. Why does a big book dropped from a big height make a louder sound when it

hits the table than a single sheet of paper dropped from low down?85. What is wrong with this student’s explanation…

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Climbers get tired when going up a mountain because they transfer all their energy into their gravitational potential energy store. This means they run out of energy and have to eat more food.When they go down mountains, they do not need to eat as much because the gravitational potential store goes into them making them feel hotter.

86. Cut bits out of this example to write your own explanation of why climbers get tired quicker when they climb uphill.

Investigating gravitational potential energy store This practical will most likely be run as a class demonstration.

Use the following structure strip below to write a plan for this investigation.87. Hypothesi

s being tested? (simple statement stating a relationship)

The gravitational potential store of a water bomb affects the width of the splash zone.



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Example answer for why a car uses more fuel driving up hill than down.As a car drives up hill it: transfers energy from the chemical store of its fuel… via the mechanical work done pathway… into the kinetic store and gravitational potential store of the car. Energy is also transferred to the thermal store of the car and its

surroundings As it goes downhill it: the car transfers energy from both its chemical store and its

gravitation potential store… into the kinetic store of the car. Energy is also transferred to the thermal store of the

surroundings.


1)

2)

3)


1)

2)

3)

4)

5)

6)

108. Risk assessment(3 most obvious hazards in your experiment and how you will reduce their risk)

1)

2)

3)

There are two factors we can change on Earth that affect the gravitational potential store of the water balloon. Complete the table for both.

Height balloon is dropped from (cm)

Width of splash zone

(cm)Mass of water

balloonWidth of

splash zone (cm)

Small

Medium

Big

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Remember that categoric variables can only have certain values. Word labels are always categoric variables. A variable that can potentially have any number value is called a continuous variable.We plot categoric variables using a bar chart. We use a line graph for continuous variables.

114. Which independent variable is categoric? Which is continuous?115. What sort of graph/chart would you use for each table? Why do you say this?116. Think of two things you might do to improve the investigation?

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Chemical store Chemical energy can be stored in the bonds of atoms and molecules – it is the energy that holds these particles together. Stored chemical energy is found in: batteries glucose food any fuel we burn e.g. petrol, coal, oil, woodAerobic Respiration (oxygen + glucose carbon dioxide + water) transfers chemical energy store into useful energy for living things.Photosynthesis (carbon dioxide + water oxygen + glucose) uses chloroplasts in leaves to transfer energy into the chemical store of glucose.

117. Which of these sources stores chemical energy? Charging your mobile phone An energy drink An exothermic reaction (one that

releases heat) Anaerobic respiration

Rocket fuel A beam of light118. This is an energy transfer diagram for a battery powered torch. Use it to explain

why eventually batteries run out and need to be replaced.

Comparing chemical energy store in different exothermic reactions

Remember that Exothermic reactions release energy. When they take place they feel hot, give off light or both. This energy was stored in the chemical energy store of the reactants. The total chemical energy store decreases.In endothermic reactions, energy is taken in to build new chemical bonds. The total chemical energy store increases. Photosynthesis is an example of an endothermic reaction.

Experiment 1: Combustion reaction

Experiment 2: RespirationCarefully put a

thermometer under

Experiment 3: Acid + Metal reaction

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your arm pit. Do not put against skin.

119. In your opinion, which reaction gives off the most energy? Why do you say this?120. In your opinion, which reaction gives off the least energy? Why do you say this?Thermal store

All objects have a thermal energy store. The hotter they are, the more they have. It is stored as the movement of particles in the object. The average energy per particle is known as temperature.

Temperature and heat are not the same thing.

A bath (lots of particles) at a low temperature may have a larger total thermal store than a cup of water (less particles) at a high temperature .

121. Which of these situations begins with a thermal store as the input energy type? A bonfire burning Cooking an egg on hot rock A volcano ejecting lava An electric heater The Sun heating our faces Sweating during exercise

Investigating relationship between thermal store and temperature

The energy transfer diagram for this experiment is shown below.

By keeping the heating time the same then the total amount of energy transferred to the water will be the same.


1)

2)

3)

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Volume of water (ml)

Temperature of water after 2 min (C)

100

20

Elastic store Some objects can change shape reversibly. Rubber balls, springs and elastic bands are like this. When a rubber ball is stretched or squashed, it can regain its shape again. We say they behave elastically. Elastic potential energy is stored in stretched or squashed materials.

128. Which of these situations contains an elastic energy store? Stretching a catapult A trampoline Squashing a spring Squashing some plasticine Stretching some chewing gum Hopping on the floor

Investigating the elastic energy store of strawberry laces Hypothesis: Strawberry laces can hold a large elastic energy store before breaking.

129. Draw an energy transfer diagram for this lace being stretched by the hanging mass.

130. Hypothesis being tested? (simple statement stating a relationship)

Strawberry laces can hold a large elastic energy store before breaking.


132. Dependent variable (you will measure )

133. 3 control variables (ensures only the IV affects the DV – makes it fair)

1)

2)

21

Do not pick same measuring device (ruler)

3)

22


1)

2)

3)

4)

5)

6)


1)

2)

3)

157. Record your results as Trial 1. Collect results from other groups for Trial 2 and 3.Mass hanging

on lace (g)Length of lace (cm)

Trial 1 Trial 2 Trial 3 Average

158. Are there any anomalous results (ones that do not fit the pattern)? Circle any you might have.

159. What sort of errors cause anomalous results? Tick the correct box Random errors – ones we cannot predict Systematic errors – ones we can

predict160. What should we do with anomalous results?161. Calculate the mean average value for the distance the block is pushed for each


test + 3rd test) ÷ 2162. Plot a line graph of Mass hanging on lace (g) vs Length of lace (cm).

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163. Draw your line or curve of best fit. Remember it doesn’t have to touch any of the points at all.


As ‘mass hanging on lace’ increases the ‘length of lace’ { increasesdecreases




165. Complete MultiChoice Questions Topic 7.1b. List 5Qs you are happy with and 5Qs you are not.

166. Extended writing challenge. You score points by using key words. You can use words more than once.The Bayeux Tapestry suggests that King Harold was killed by an arrow in the eye at the Battle of Hastings in 1066. Arrows have had an important part in shaping our history.At one point the archers of England were so important that all other hobbies were banned and everyman had to practice archery every Sunday.Pulling a bow is hard work. Use your knowledge of energy to explain why archers were sometimes given extra food rations during war.

1 Point: Conservation of

energy Chemical store of

archer Respiration

2 Points: Kinetic store of

arrow Glucose Oxygen

3 Points: Gravitational

potential store of arrow

Thermal store Mitochondria in

cellsEnergy transfers along pathways

Remember that: The law of conservation of energy states that energy cannot be created or destroyed. It is only moved from one store to another.Energy can move between the 8 energy stores using pathways. There are only 4 energy pathways. We can remember them using the mnemonic 4 Mr He. We cannot store energy in pathways.

4 Mr He

Mr

Mechanical work done – moving a forceradiation (light, sound, infra-red)

He

Heat (via conduction through contact)electrical work done (current)

167. Look at the KO Questions. Practice Look, Read, Cover, Write, Check for 5 minutes. Then work with your partner and test each other for another 5 minutes.

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Write a list of the 5Q numbers you are most confident with. Write another list with the 5Q you are least confident with.

168. What is the Law of Conservation of energy?169. What are the Units we measure energy in? Who are they named after?170. What is the mnemonic we use to remember the Energy Stores? What are they?171. What is the mnemonic we use to remember the Energy Pathways? What are

they?

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172. What energy transfer is needed to score a goal in the top corner? Tick the correct statement below.

A chemical store → kinetic store B kinetic store → gravity store C chemical store → gravity store + kinetic store D kinetic store → gravity store + heat store E chemical store → gravity store + kinetic store + heat store

173. Which of these scenarios shows energy being transferred to a new store?A person taking a nap

Transfer to a new store

No transfer of energy

Packet of crisps Transfer to a new store


Rock on top of a cliff Transfer to a new store


A person after a long run

Transfer to a new store


Ball rolling uphill Transfer to a new store


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Misconception with Work Done In Science, the term ‘Work Done’ has a very different meaning than it does in everyday life. This causes difficulties and we must be careful. In science, ‘Work done’ or ‘Work’ refers the amount of energy transferred from one store to another. It has nothing to do with the type of task or how much you enjoy it. These statements therefore are incorrect in science: I only do work in class. Writing a page is more work than playing netball because I

prefer netball.These statements would be the correct versions: Whenever I exert a force and something moves, I am

transferring energy as mechanical work done. Both writing and netball require a force to move and both

transfer energy from my chemical store to my kinetic store. Therefore, both involve mechanical work.

174. In science what must we be talking about when we use the term ‘Work Done’ or ‘Work’?

175. Lucy is freewheeling down a steep hill.

Some of her kinetic energy store is being transferred by mechanical work done against friction to a heat store. Where is work being done in energy transferred by friction to a heat store?For each place, tick () one column to show what you think.

Places I am sure this

I think this is

I think this is

I am sure this

A The brakes B The tyresC The airD Her feet

Mechanical Work Done Pathway Energy can be transferred mechanically when an object moves or when the motion of object changes. Here are two common examples of mechanical work done occurring: When an object falls (moves) mechanical work done moves to

kinetic store of object and thermal store of surroundings When something moves against friction mechanical work

done moves to thermal store of object and surroundings176. Which situation transfers energy via the mechanic work done pathway?

Stretching a catapult A car accelerating Skidding on the gravel Squashing some plasticine An electric fire A bonfire

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Radiation pathway Energy is carried in waves which have no mass. The two groups of waves which have no mass are sound waves and the waves of the electromagnetic (EM) spectrum. All electromagnetic waves travel at the speed of light and can travel through a vacuum like space. Our Sun gives off all the waves of the electromagnetic spectrum.The three waves we observe most often as radiation pathway are sound, visible light and infra-red.

177. What is the mass of energy carried by the radiation pathway?178. Which of the following are examples of radiation pathway?

a) Sound b) Light c) Gamma rays d) X-rayse) Water waves f) Mexican wave g) Ultrasound

wavesh) Infra-red rays

Heat Pathway Some objects are hotter than others. Energy is always transferred from the hotter object to the cooler one. This is known as the Zeroth Law of Thermodynamics. The difference in temperature between two objects always get less.Heat is not the same as infra-red radiation. For energy to be transferred by the heat pathway there needs to be particles which move with by conduction (solids) or convection (liquids and gases)

Metals are excellent conductors of heat because they are usually solids and have electrons that can move. This is because they have 1, 2 or 3 electrons in their outer shell (are in Groups 1,2 or 3 in the Periodic Table). Remember that all atoms (apart from H and He) would like either 0 or 8 electrons in their outer shells. So, it is easier to lose 1, 2 or 3 than gain 7,6 or 5.

Non-metals are not as good at conducting as their electrons are not free. This is because they have 5, 6, 7 or 8 electrons in their outer shell so it is easier for them to fill this shell rather than empty it.

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Hydrogen and elements with 4 electrons in their outer shell (Group 4) sometimes behave like metals and sometime as non-metals which is why they are so useful.All gases are poor conductors. Poor conductors are called insulators.

179. Why are metals good conductors of heat?180. Why are non-metals good conductors of heat?181. What are Groups in the Periodic table? What have they got to do with

electrons?182. Why are Group 4 atoms so interesting?183. What does the term insulator mean?184. How many electrons do all atoms (except H and He) want in their outer

shell?185. Why are elements in Groups 5, 6, 7 and 0 always non-metals?Electrical Work Done Pathway

Energy is transferred when an electrical circuit is complete. A simple circuit may consist of a battery, lamp and wires. Electrical work done is also known as current. Our brains rely on using electrical work done to send electrical signals around our central nervous system. This is one of the reasons we need so much food to keep our chemical energy store high enough.Metals are all good conductors of electrical current because their electrons can move. This is because they have 1, 2 or 3 electrons in their outer shell (are in Groups 1,2 or 3 in the Periodic Table). Non-metals (except Graphite which is a form of Carbon in Group 4) are poor conductors.

186. Why will this battery never run out of its chemical energy store?

187. Draw a series circuit containing a battery and two lamps. Use correct circuit symbols.

188. Draw a parallel circuit containing a battery and two lamps. Use correct circuit symbols.

189. What are the units of current?190. What device do we use to measure current?191. What is the difference between series and parallel circuits?Dissipation of energy and efficiency

In any activity, energy is always transferred to the thermal energy store of the surroundings. We call this process dissipation. Every energy transfer diagram should have thermal energy store of surroundings as an output. This is

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normally a ‘wasted’ energy store as it is usually not the one we are intending to increase.The energy store we would like to increase is known as the ‘useful’ energy store. The better an activity is at transferring the energy from the input store to the useful store, the more efficient it is.Efficiency is always a number between 0 and 1. Sometimes it is written as a % (between 0% and 100%). It has no units. We can measure efficiency using the equation:Efficiency = Useful energy store ÷ Input energy store

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The words Efficient and Effective are often confused. Efficient is a measure of how good something is at not wasting energy. Effectiveness is a measure of whether something can transfer any energy to the useful energy store or not.

192. What does dissipation mean?193. Which type of activities dissipate energy to the surroundings?194. What do we call energy transferred to stores that are not the one we intended? 195. Efficient, effective or both?

Efficient

Effective

a) Riding a bike with a flat tyreb) Energy efficient light bulbsc) A steam train going up hilld) Using your body heat to boil water

196. Calculate the efficiency for each of these activities:Input energy store (J)

Output energy store (J)

Efficiency

a) Energy efficient light bulb 12 6b) Old style filament light bulb 60 6c) A modern car 16 000 2 400d) A person cycling 500 100e) A coal powered power station 10 000 000 3 000 000

197. What is the Law of Conservation of energy?198. What are the Units we measure energy in? Who are they named after?199. What is the mnemonic we use to remember the Energy Stores? What are they?200. What is the mnemonic we use to remember the Energy Pathways? What are

they?201. Complete MultiChoice Questions Topic 7.2a. List 5Qs you are happy with and

5Qs you are not.202. A perpetual motion machine is a one that would work forever without an

energy source. This means it would waste no energy. Science does not believe that such machines are possible.Describe why even a nuclear-powered spaceship would eventually need re-fuelling [6].Use this structure strip to help

What the energy store does the submarine use?What is the main useful output energy store?Which pathway would it use?What output energy stores

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are involved?Which of these other output stores are wasted energy?Why would this eventually mean that more nuclear fuel would be needed?

Modelling energy transfers We draw energy transfers using an energy transfer diagram. There are lots of different formats but this is the type we use most often.

Notice that it always starts and ends with energy stores. Thermal store of the surroundings is at the end of every energy transfer diagram for a system.

203. In our normal energy transfer diagrams, what shape do we use to represent energy stores?

204. In our normal energy transfer diagrams, what shape do we use to represent energy transfers? Why is this a good shape to use?

205. What is the law of conservation of energy?206. What the mnemonic we use to remember the different energy stores?207. What are the different energy stores?208. What the mnemonic we use to remember the different energy

pathways?209. What are the different energy pathways?Here are two more models for showing different energy transfers.Model 1 Model 2: Called a Sankey diagram

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The thickness of each arrow represents the quantity of energy.

210. Compare the two models using the graphic organiser below

211. What is this energy transfer diagram showing?

212. Here is an energy transfer for photosynthesis. What is the word equation for photosynthesis?

213. Which part of a plant cell is responsible for carrying out photosynthesis?214. Here is an energy transfer for respiration in a person. What is the word equation

for respiration?

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215. This Sankey diagram describes the energy transfers occurring as a meteorite falls to Earth. Label it with as much information as you can in 60 seconds.

216. What part of a cell is responsible for carrying out respiration?217. What is the Law of Conservation of energy?218. What are the Units we measure energy in? Who are they named after?219. What is the mnemonic we use to remember the Energy Stores? What are they?220. What is the mnemonic we use to remember the Energy Pathways? What are

they?221. Draw an energy transfer diagram for:a) A book falling through air b) A moving book hitting a deskc) A fire burning d) A bow firing an arrow forwarde) A mobile phone playing music f) A paperclip being pulled by a magnet g) A hot kettle cooling on a cold day h) The Sun warming i) A mars bar you are about to eat j) Your wool jumper crackling when you

take it off222. What happens when Liam lifts the book onto a high shelf?

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Which Sankey diagram best shows what happens? Put a tick () next to the correct answer.

223. Look at the KO Questions. Practice Look, Read, Cover, Write, Check for 5 minutes. Then work with your partner and test each other for another 5 minutes. Write a list of the 5Q numbers you are most confident with. Write another list with the 5Q you are least confident with.

Energy transfer circus Use the instructions below to build energy transfer diagrams.Instructions Support224.

225.

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226.

227.

228.

229.

230. One theory for the extinction of dinosaurs was that a meteor hit Earth and created a dust cloud that blotted out the Sun.Describe how the Sun is the source of energy for all living things on Earth [6].Use this structure strip to help.

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Describe the Energy Store of the Sun

The Sun stores energy as…

It transfers it to Earth by…

Which Organisms capture this energy to make their food? How do they store it?

This energy is used by ….

They store it as

What process do they use?

They do this by a process known as…

How is this energy passed to other organisms? Which pathway is this?How do other organisms store this energy?What would happen to all the organisms if the Sun didn’t shine?

Investigate a factor that affects how high a ball bounces

Use the following structure strip to plan your investigation.231. Hypothesi

s? (simple statement stating a relationship you can test)

233. Independ37

ent variable (you change)



1)

2)

3)


1)

2)

3)

4)

5)

6)


1)

2)

3)

We will now test the following hypothesis: “The lower the ball is dropped from, the higher it bounces”259. Record your results here:Height ball is Height bounce (cm)

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dropped from (cm) 1st test 2nd test 3rd test Mean100806040200

260. Why was it important to make sure you always measured the height from the same point on the ball (top or bottom)? How might changing this, changed your results?

261. Are there any anomalous results (ones that do not fit the pattern)? How can you tell? If you have some put a circle around them. Random errors – ones we cannot predict Systematic errors – ones we can

predict262. What should we do with anomalous results?263. Calculate the mean average value for each bounce height.

Be careful to round your answer to 1dp using mean = (1st test + 2nd test + 3rd test) ÷ 3 Remember to ignore anomalies e.g. If 2nd test result is anomalous then mean = (1st test + 3rd test) ÷ 2

264. Plot a graph of Height ball is dropped from (cm) vs Mean Height of bounce (cm). It should look something like this when complete

265. Draw your line or curve of best fit. Remember it doesn’t have to touch any of the points at all.

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As ‘height of ball is dropped from’ increases, the’ height of bounce’ { increasesdecreases




267. Predict how high the ball would bounce if we dropped it from 120cm. Describe how you came up with this prediction.

268. Does your investigation support the hypothesis: “The lower the ball is dropped from, the higher it bounces”? Why do you think that?When we want to test a result to see if it is reliable or not, we often use repeats. A result that is repeatable and reproducible is considered reliable.

269. If other people in your class got the same results as you using a different technique (e.g. different ball) would that make your results repeatable or reproducible? Say why?

270. Why might we be suspicious of the results from a bouncy-ball manufacturer?271. Complete MultiChoice Questions Topic 7.2b. List 5Qs you are happy with and

5Qs you are not.272. Draw an energy transfer diagram for the ball in these three stages of its fall and

bouncea) Just been released from

1m.b) Just about to hit the floor.

Maximum velocity downwards.

c) On the floor, just stopped moving downwards and is beginning to move upwards.

d) At the top of its bounce

273. Why does the ball eventually stop bouncing? Where does all its original energy store go?

274. Extended writing challenge. You score points by using key words. You can use words more than once.Old clocks use pendulums instead of batteries to run.A pendulum is lifted up and swings.Eventually all pendulums

1 Point: Gravitational Potential store Kinetic store Thermal store

2 Points: Air resistance Dissipated

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RepeatableSimilar results

using same method

ReproducableSimilar results using

different method

stop, no matter how high they are lifted or how heavy they are.Use your knowledge of energy transfers to explain why this is.

3 Points: Particles Efficiency

275. Compare these two scenarios similar in terms of energy transfers?Scenario 1

Squash is a ball game where you hit a small ball against a wall. During a game of squash, the ball heats up. The more vigorously the players play, the quicker the ball heats and the hotter it gets.

Scenario 2Formula 1 cars travel very fast. When they need to slow down their brakes squeeze and apply a friction force to their wheels. When they do this, the brakes get very hot.

276. For each activity below draw an energy transfer diagram and name the wasted energy stores.a) Someone

kicking a football

b) A solar powered car

c) A windmill turning

d) A rollercoaster rolling down a slope

e) A BBQ cooking some corn

f) A candle lighting a room

g) A battery powered TV

h) A girl hitting a golf ball as far as she can

Power Some objects transfer energy much quicker than others. The measure of how quickly energy is transferred is called Power.

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Both funnels transfer the gravitational store of the liquid into the kinetic store of the liquid. Funnel A will do this in a shorter time so is higher power.In science we are careful not to use the word speed here as speed relates to the change in distance. Power is the rate at which energy is transferred.

James Watt was a Scottish engineer. He came up with the term Horsepower to describe the rate at which a device could transfer energy. A 1 horsepower steam engine could transfer energy as quickly as one draft horse. We no longer measure energy in terms of horses and instead use the unit Watts (W). One Watt is the same as One Joule transferred every One second.

Interestingly a power of one Watt is roughly equal to 750 horsepower.

The equation for calculating power in Watts is: Power = Energy transferred ÷ time (W) (J) (s)Watts (W) are the same as Joules per second (J/s). This is sometimes easier to think of as Joules each second (J/s).A 60W light build therefore transfers 60 Joules of energy each second.

277. What are the units of power?278. Who are the units of power named after? 279. Why would it not be polite to use a lower-case letter for the units of Power,

Energy, Force, Current or Potential difference?280. Which has the highest power. Say why you think that.

a) A bright light or a dim one? b) A loud mobile phone or a quiet one?c) A burning match or an explosion? d) A walker or a runner?e) A solar cell storing 100Joules in

20seconds or a wind turbine storing 100Joules in 50seconds?

f) Wave transferring 200Joules in 10seconds or a dam transferring 400Joules in 10seconds?

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Generating electricity and energy resources Our civilisation depends on the energy transferred by electrical work done. Trying to find new sustainable ways of generating electrical power is one of the biggest modern challenges to human-kind.The different sources we will consider all have different pros and cons. Many use different energy stores so we must use different technology to transfer it.Broadly, there are two main groups of energy resources: Non – renewable sources – these will eventually run out. They

are used more quickly than they are replaced. Renewable sources – these will not run out. They are replaced

more quickly than they are used.281. What is the mnemonic we use to remember the different energy stores?282. What are the different energy stores?283. Silent Debate. You will work in a group of 3 or 4 people. Each needs a different

coloured pen.Rules: #1 You must write on each others sheets #2 Write in clear English no text-speak or abbreviations. #3 Stay on topic. #4 You must be silent. You can only write your argument points down on this paper. #5 Use arrows to challenge specific points and write next to them.Question to debate:

Sustainability, climate change and the greenhouse effect Sustainability considers the impact of decisions on future

generations. If something is sustainable then it will not run out or cause significant problems in the future.

Global warming is a term for the Earth getting hotter over time. We measure average annual temperatures and compare against previous years. There is a very strong body of evidence to suggest the Earth is warming.

The greenhouse effect is the most agreed on theory for what is causing global warming. It suggests that Carbon Dioxide and other greenhouse gases are creating an insulating layer around Earth which prevent it from cooling as it should. Be careful not to confuse it with the Ozone Layer which is very different.Climate change describes the changing weather patterns which are happening due to global warming.

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Our demand for electrical power is growing. Should our priorities be finding new power sources; making current ones less damaging, or in reducing our

consumption?

284. Complete this quick comparison of non-renewable and renewable energy sources:

285. Complete MultiChoice Questions Topic 7.3a. List 5Qs you are happy with and 5Qs you are not.

Non-renewable sources Non – renewable sources – these will eventually run out. They are used more quickly than they are replaced.There are two main types of non-renewable sources: Fossil fuels – Coal, Oil and Gas – we are running out of these

already. Petrol and diesel in cars are made from these. Aeroplane fuel is also made from fossil fuels.

Nuclear fuel – Plutonium and Uranium – although these will eventually run out, they will still last many millions of years so we are less worried.

Fossil fuels Fossil fuels are non-renewable sources – these will eventually run out. They are used more quickly than they are replaced.There are three types of fossil fuel and all were made in similar ways to each other.

Coal (and charcoal) is made from the remains of prehistoric trees – you can actually still see the wood grain in lumps of coal.

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Crude oil (sometimes just called oil) and natural gas (sometimes just called gas) are made from remains of prehistoric animals, plankton and algae.The fossil fuels are made from compounds known as hydrocarbons such as Methane (CH4) and Ethane (C2H6). These molecules only contain hydrogen and carbon.The fossil fuels all act as a chemical energy store. It is relatively easy to transfer this energy into electrical work done by burning them. Burning (or combustion) is an exothermic chemical reaction with oxygen.When we burn hydro-carbons we release carbon dioxide (CO2) and water (H2O). Carbon dioxide is a greenhouse gas and contributes to global warming. Methane + Oxygen Carbon Dioxide + Water CH4 + O2 CO2 + H2O Not balancedHow to balance equations, reminder:1. Rewrite molecules without subscripts and box

CHHHH + OO COO + HHO

2. Need same number of C, H and O on each side of arrow but can only add whole boxes.

CHHHH + OO COO + HHO

OO HHO 3. Add number of boxes into original formula in front of molecules:

CH4 + 2O2 CO2 + 2H2O286. Why do we call fossil fuels non-renewable?287. Compare how coal, crude oil and natural gas were formed:

How

coa

l w

as fo

rmed

How

oil

and

gas

wer

e fo

rmed

Different Similar Different288. Label this energy transfer diagram for using a fossil fuel to generate electrical

work done.

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289. Complete this pros and cons dial for using fossil fuels to generate electricity. Add an arrow to show your final opinion.

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290. Add as much information as you can to this diagram to explain how fossil fuels are created.

Look at these different moleculesa) HCl b) H2O c) O2 d) CH4e) CO2 f) CO g) C2H6 h) C6H12O6

291. How many different elements are in each molecule above?292. How many different atoms are in each molecule above?293. Which of the molecules above are released when we burn hydrocarbon fossil

fuels?294. Write a word equation for the combustion reaction of Ethane (C2H6) in air.295. What is an exothermic reaction?

Greta Thunberg

In August 2018 Greta Thunberg, a Swedish Teenager staged her first "School Strike for Climate" in front of the Swedish Parliament. Within a year she had met World Leaders and started an international youth movement against climate change. Her strike has inspired students from around the world, leading tens of thousands of students from Germany, Japan, the UK, Australia and many more to join her #FridaysforFuture demonstrations.

Around 2014 she was diagnosed with Asperger’s, a form of autism but considers this as a strength as "Being different is a gift,"… "It makes me see things from outside the box. I don't easily fall for lies, I can see through things. If I would've been like everyone else, I wouldn't have started this school strike for instance."

One of her areas of focus is the release of carbon dioxide from the continued burning of fossil fuels. Carbon dioxide builds up in the atmosphere, which prevents the Earth cooling as it normally would in a similar way to a Greenhouse. This in turn leads to increased planet temperatures and Global Warming (which is also known as the Greenhouse Effect). Rising sea levels and climate change are both believed to be caused by Global Warming.

296. Silent Debate. You will work in a group of 3 or 4 people. Each needs a different coloured pen.Rules: #1 You must write on each other’s sheets #2 Write in clear English no text-speak or abbreviations. #3 Stay on topic.

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#4 You must be silent. You can only write your argument points down on this paper. #5 Use arrows to challenge specific points and write next to them.

Nuclear fuel Nuclear fuels are non-renewable sources – these will eventually run out. They are used more quickly than they are replaced.

We are less worried about nuclear fuels running out as we use them so slowly that they will last millions of years. Uranium (U) and Plutonium (Pu) are the two main types of nuclear fuel we use.We use a nuclear reactor to transfer the fuels nuclear energy store into heat which we then use to heat water to turn a turbine and generate electricity. Nuclear power stations generate huge amounts of electricity (high yield) and no greenhouse gases are produced. They are also very reliable.

The UK currently has 15 nuclear power station reactors operational and is planning to build more as it tries to move away from fossil fuel power.

Both the fuels and the waste from nuclear power are radioactive. This means they are very dangerous and expensive to control.Nuclear power accidents are very rare, but many people remain scared.

There have only been two major (category 7) accidents but both are well known:

1) Fukushima,2011: a nuclear reactor in Fukushima, Japan was hit by tsunami caused by an earthquake. It culminated in a meltdown and is believed to have killed around 19,000 people. The area surrounding Fukushima is still highly radioactive, and 30,000 people are still unable to return to their homes.

2) Chernobyl, 1986: during a safety test an accident at Chernobyl, Ukraine led to a meltdown of Reactor Number 4. The radioactive dust from the explosion was carried across Northern Europe by the wind and it is predicted that between 9,000 and 16,000 fatalities were caused as a consequence. The whole city is still abandoned.

297. What are the two most common nuclear fuels?298. Is nuclear fuel renewable or non-renewable? What does this mean?299. Does nuclear power contribute to global warming? Why do you say this?300. Which energy store does Uranium store?

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Questions: Should all the countries of the World be working together to try and reduce the amount of fossil fuels we are burning? Why don’t we just

keep going until they are all gone?

301. Complete this comparison between coal and nuclear power

302. Complete this pros and cons dial for using nuclear fuel to generate electricity. Add an arrow to show your final opinion.

303. Extended writing challenge. You score points by using key words. You can use words more than once.All our electricity is generated somewhere and transported to our homes via the National Grid.The government is trying to reduce our dependence on fossil fuel power stations. One option is more nuclear power stations.Explain why the government are considering this change and what issues there might be. The UK National

Grid

1 Point: Renewable Non-renewable Greenhouse gases

2 Points: Carbon dioxide Fuel Electricity yield

3 Points: Radioactive Risk


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Renewable sources Renewable sources – these will not run out. They are replaced more quickly than they are used.Misconception 1: many people wrongly state that renewable means they can be used again. This is not correct. Once I burn some wood, I cannot reuse the same wood. I can however, grow some more wood and provided I can do that quicker than I use it, it is renewable.Misconception 2: People think renewable sources are perfect and have no problems. This is not true. Biofuels for instance still release carbon dioxide when burned.

305. What does renewable mean?306. What does non-renewable mean?307. What are the four non-renewable fuels?Biofuels

Biofuels are a renewable source – they will not run out. They are replaced more quickly than they are used.Bio – means life or living. Biofuels are fuels that have been grown or produced from living organisms. There are lots of different types of biofuels: Wood Food waste Ethanol from plants and cereals Methane from bacteriaWe burn biofuels in a similar way to fossil fuels. They also release carbon dioxide which is a greenhouse gas.Some biofuels are considered carbon neutral. This is because the amount of carbon dioxide they absorb as they grow is equal to the carbon dioxide they give off when they are burnt. This often ignores the effects of planting, harvesting, processing and transporting all of which can lead to more carbon dioxide being released.Using waste as a biofuel is also an effective way to avoid waste going in to landfill.Growing special biofuel crops and trees requires land. This means that this land cannot be used to grow food.

308. Name four biofuels.

309. How does the biofuel logo help to remind people what biofuel is?310. Is biofuel renewable or non-renewable? What does this mean?311. Does burning biofuels contribute to global warming? Why do you say this?312. Which energy store do biofuels store?

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https://en.wikipedia.org/wiki/File:Biofuel_-_The_Noun_Project.svg

https://en.wikipedia.org/wiki/File:Biofuel_-_The_Noun_Project.svg

313. Biofuels are sometimes call carbon-neutral. What does carbon-neutral mean?

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314. Complete this comparison between crude oil and biofuel-oil power.

315. Complete this pros and cons dial for using biofuels to generate electricity. Add an arrow to show your final opinion.

316. Complete MultiChoice Questions Topic 7.3b. List 5Qs you are happy with and 5Qs you are not.

Wind and wave power Wind and wave are renewable sources – they will not run out. They are replaced more quickly than they are used. Both wind and wave are caused by the wind. They transfer the kinetic store of the air or water into mechanical work done in turning a turbine and generator.They are unreliable as they need wind or waves to operate. When they are running they generate low quantities of electricity compared to most other generation techniques.Some people do not like how they look (we call this visual pollution) and some worry that they have a negative impact on animals living around them.They do not release any greenhouse gases.

317. Why are wind and wave described as unreliable?318. What does the term renewable resource mean?319. What are the mnemonics to remember the energy stores and energy pathways?

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320. List the energy stores?321. List the energy pathways?322. What is the law of conservation of energy?323. Nuclear power generates more electrical power than wave power. What is power

a measure of? What are its units?324. Complete this pros and cons dial for using wind or wave power to generate

electricity. Add an arrow to show your final opinion.

Tidal power and hydro-electricity Tidal and hydro-electric are renewable sources – they will not run out. They are replaced more quickly than they are used.Both tidal and hydro-electric work by trapping water high up then allowing it to flow down through a turbine. They transfer the gravitational potential store of the water into mechanical work done in turning the turbine and generator.Tidal power catches sea water when it is high-up during high tide. It is very predictable but can only release water and generate electricity when the tide is low.Hydro-electric catches rain water which it stores in dams. It relies on rain so can be more unreliable during extremely dry periods. Once the water is stored, it can be released quickly and electricity generated immediately. It has a very short start-up time because of this.Both tidal and hydro-electric can damage habitats as they require areas to be flooded. Neither release any greenhouse gases.

325. What are the 4 different energy pathways?326. What is the law of conservation of energy?327. What are the units of energy? Why should we always use a capital letter for

them?328. Power stations are often effective but not very efficient. What does this mean?329. Complete this energy transfer diagram for a tidal or hydro-electricity power

station.

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330. Complete this comparison between tidal and hydroelectric power.

Solar power Solar power is renewable - it will not run out. It is are replaced more quickly than it is used.All life on Earth depends upon the Sun for its energy to live. In terms of using it to generate power from directly, there are two techniques we use: Infra-red – We use its energy to heat water Photovoltaics – we use solar cells which transfers energy carried

by light directly into an electrical currentSolar power is very unreliable as it requires sunlight. It can only be used in the daylight. It does not release greenhouse gases.The Sun is the nearest star to Earth and is at the centre of our Solar System. It transfers its enormous nuclear energy store to Earth via radiation which we experience as light and infra-red radiation.Between Earth and the Sun is space. Space is a vacuum, this means that there are no particles at all. There is still gravity in space. It is the Sun’s gravity which causes Earth to spin around it rather than shoot into space.

It is so far way that the light from it takes 8minutes and 20seconds (500seconds) to reach us. If we consider that light travels at 300 000 000m/s (that’s 300 000 000 metres each second) it is a very long way.

The next nearest star to Earth is called Proxima Centauri. It is so far that light takes 4.24 years (133 712 640 seconds) to reach us. This is so far that we do not use metres of km to measure it. Instead we say it is 4.24 light years away i.e. the same distance light would travel in 4.24 years.

331. What is a vacuum?332. Is there gravity in space?333. What energy store does the Sun transfer?

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334. Complete this comparison between solar power and biofuel power.

335. Complete this pros and cons dial for using solar power to generate electricity. Add an arrow to show your final opinion.

Geothermal power Geothermal power is renewable - it will not run out. It is are replaced more quickly than it is used.‘Geo’ comes from the Greek for ‘Earth’ and ‘thermal’ comes from the Greek for ‘heat’. ‘Geothermal’ therefore means ‘Earth-heat’.Deep beneath the surface of the Earth are hot radioactive rocks. These rocks have vast thermal energy stores. In certain parts of the World there are deep cracks in the Earth’s crust which sometimes allows molten rock (lava) to escape in volcanoes. We can use this natural heat source to heat water and generate electricity. Cold water is pumped down and hot water returns.

No greenhouse gases are released. It is reliable and can give high output. Only certain locations on Earth are suitable for this to power generation.

336. What does the term geothermal mean?57

337. Why can’t we use geothermal power anywhere on the Earth?338. Complete this energy transfer diagram for Geothermal power station which uses

hot steam to spin a generator.

339. Complete this comparison between geothermal and nuclear power.

340. Complete this pros and cons dial for using geothermal power to generate electricity. Add an arrow to show your final opinion.


342. Silent Debate. You will work in a group of 3 or 4 people. Each needs a different coloured pen.Rules: #1 You must write on each others sheets #2 Write in clear English no text-speak or abbreviations. #3 Stay on topic. #4 You must be silent. You can only write your argument points down on

58

this paper. #5 Use arrows to challenge specific points and write next to them.

Knowledge Organiser Questions KQ.1. What do we call the law which states that:

“Energy cannot be created or destroyed. It is only moved from store to another”

Law of conservation of energy

KQ.2. What are the units of energy? Joules or JKQ.3. What is the mnemonic we use for the different

energy stores8 kg cement

KQ.4. Which energy store is associated with a moving object?

kinetic store

KQ.5. Which energy store is associated with an object high up?

Gravitational potential store

KQ.6. Which energy store is associated with a battery?

Chemical store

KQ.7. Which energy store is associated with food? Chemical storeKQ.8. Which energy store is associated with a fuel? Chemical storeKQ.9. Which energy store is associated with a

squashed spring?Elastic potential store

KQ.10. Which energy store is associated with the Sun?

Nuclear store

KQ.11. Which energy store is associated with a hot object?

Thermal store

KQ.12. What is the mnemonic we use for the different energy pathways?

4 Mr He

KQ.13. Which pathway is involved when an object moves and experiences friction?

Mechanical work done

KQ.14. Which pathway is involved when an object is lifted up?


KQ.15. Which pathway is involved when an object falls through the air?


KQ.16. Which pathway is involved when the chemical store of a battery moves to the thermal store of a heater?

Electrical work done

KQ.17. Which pathway is involved in transferring energy from the Sun to Earth?

Radiation

KQ.18. Which pathway is involved in transferring energy stored in your body to an ice cube in your hand?

Thermal

KQ.19. Draw a simple energy transfer diagram for a wood fire heating a room

KQ.20. What is the name of the variable you change in an investigation?

Independent variable

KQ.21. What is the name of the variable you measure in an investigation?

Dependent variable

KQ.22. An experiment where only the independent variable affects the dependent

Fair test

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Question to debate: If you had £100billion to invest in delivering power to your school. Which source(s) would you pick? Which sources

wouldn’t you pick? Why?

variable KQ.23. What sort of graph/chart do we use for

categoric variables?A bar chart

KQ.24. What sort of graph/chart do we use for continuous variables?

A line graph (with line of best fit)

KQ.25. What do scientists do to increase confidence that everyone agrees with their conclusions?

Share results

KQ.26. Is there gravity in space? Yes (everywhere)KQ.27. If you are using a glass apparatus in an

experiment, what risk should always be included in your plan?

Glass might break and cut you

KQ.28. What do we call results that do not fit the pattern of the rest?

Anomolous

KQ.29. Name the useful energy store in an electric toaster.

Thermal store of the toast

KQ.30. Name a wasted energy store in an electric oven

Thermal store of the surroundings

KQ.31. What do we call the process where energy is always transferred to the thermal store of the surroundings?

Dissipated

KQ.32. What is the measurement of how good something is at not wasting energy?

Efficiency

KQ.33. What is the maximum value of efficiency possible?

1 or 100%

KQ.34. What is power a measure of? Rate energy is transferred (Joules each second)

KQ.35. What are the units of power? Watts (W)KQ.36. What are non-renewable fuels? Ones that will run outKQ.37. Name the 3 fossil fuels. Coal, oil and gasKQ.38. Other than fossil fuels, name one other

non-renewable source.Nuclear

KQ.39. Approximately how long does it take to make fossil fuels?

Hundreds of millions of years

KQ.40. What gas do fossil fuels release when they are burned?

Carbon dioxide

KQ.41. Nuclear power can produce huge amounts of electricity without the worry they will run out. What is their other big advantage?

They do not release carbon dioxide

KQ.42. Uranium is one nuclear fuel. Name the other common one.

Plutonium

KQ.43. What does renewable energy sources mean?

Ones that will not run out

KQ.44. Growing biofuels takes space which could be used to grown food. Give one other disadvantage of biofuels.

Release carbon dioxide (when they are burned)

KQ.45. Biofuels absorb carbon dioxide when they grow. If they release the same amount of carbon dioxide when they are burned we call them what?

Carbon neutral

KQ.46. What energy store do both wind and wave power use?

Kinetic store (of air and water)

KQ.47. What energy store do both tidal and Gravitation potential store 60

hydro-electric power use? (of water)KQ.48. What energy store does Solar power use? Nuclear store (of the Sun)KQ.49. What energy store does Geothermal

power use?Thermal store (of the Earth)

KQ.50. As an object increases its thermal store, what happens to the particles inside it?

They vibrate faster (or break bonds holding them together)

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prior knowledge: multichoice questions · web viewthe total chemical energy store decreases. in...

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