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WESTERN CAPE PRIMARY SCIENCE PROGRAMME
ENERGY ANDCHANGE
GRADE 5
We welcome the wide use of these materials. Please acknowledge the PSP. ©PSP 2002
An example of a short learning programme in the Natural Sciences and Technology
ACTIVITIES1: Making a class poster to show
the different forms of energy
2: Electrical energy travels throughdifferent materials
3: Making electrical circuits inorder to get heat, light, soundand movement energy
4: The mains electricity alsosupplies heat, light, sound andmovement energy
5: How much electrical energy doappliances use from the mainsupply?
6: Where does the main electricitycome from?
7: How do we use electricity safely?
DEVELOPED BY WESTERN CAPE PSP TEAM AND TEACHERSThis learning programme will work towards the following learning outcomes in the Natural Sciences
K LO1: Scientific InvestigationsThe learner will be able to act confidently on curiosity about natural phenomena, and to investigate relationships and solve problems in scientific, technological and environmental contexts
K LO2: Constructing Science KnowledgeThe learner will know and be able to interpret and apply scientific, technological and environmental knowledge
K LO3: Science, Society and the EnvironmentThe learner will be able to demonstrate an understanding of the interrelationshipsbetween science and technology, society and the environment.
Course presented by Rose Thomas, Shane Nzwane and Sandra Mahote
Booklet designed by Welma Odendaal and illustrated by Janet Ranson and Nicci Cairns
Western Cape Primary Science Programme
Edith Stephens Wetland Park
Lansdowne Road
Philippi 7785
PO Box 529Howard Place7450
Tel: 021 691-9039 Fax: 021 691-6350
e-mail: [email protected]
website: www.psp.org.za
Contents• This booklet illustrates an example of a short learning programme for Grade 5.
• It develops concepts, skills, attitudes and language in a step-wise fashion.
• It includes activities and tasks for learners, teacher tasks, support materials and assessment suggestions.
2 . . . . . . . . . .Activity 1 Making a class poster to show the different forms of energy
4 . . . . . . . . . .Activity 2 Electrical energy travels through different materials
8 . . . . . . . . . .Activity 3 Making electric circuits in order to get heat, light, sound and movement energy
12 . . . . . . . . .Activity 4 We also get heat, light, sound and movement energy from the main supply
14 . . . . . . . . .Activity .5 How much electrical energy do appliances use from the main supply?
17 . . . . . . . . .Activity 6 Where does the main electricity come from?
18 . . . . . . . . .Activity 7 How do we use electricity safely?
22 . . . . . . . . .Suggested workscheme
23–26 . . . . . .Assessment sheets
27 . . . . . . . . .Codes for assessment
Task cards to photocopy
28 . . . . . . . . .Activity 2 Which materials can electricity flow through?
30 . . . . . . . . .Activity 3 Making electric circuits to get heat, light, sound and movement energy
31 . . . . . . . . .Activity 4 Light , sound , movement and heat energy
32 . . . . . . . . .Activity 5 How much electrical energy do appliances use from the main supply?
33 . . . . . . . . .Fact sheet: How much electricity is used by our appliances?
34 . . . . . . . . .Activity 7 A The 3-pin plug
35 B Using electricity safely in the home
Support materials
37 . . . . . . . . . . . . .Safety in the home
38 . . . . . . . . . . . . .How light bulbs work
38 . . . . . . . . . . . . .Background information about batteries
39 . . . . . . . . . . . . .Batteries and cells
40 . . . . . . . . . . . . .Background information about Earthing and electrical shocks
Back page . . . . . .Mindmap about energy and change
2
Making a class poster to show thedifferent forms of energy
Assist learners to find pictures from newspapers and magazines to make aposter. Assist them to identify the different forms of energy in thepictures.
• Energy exists in different forms (there are different types of energy – heat, light, sound, movement, electricity). There is also nuclear (atomic) energy and stored energy but we do not expect to cover these in this activity.
Forms of Energy
movement energy
heat energy
heat energy
electric energy
sound energy
light energy
NOTE:
We also get nuclear
energy and stored
energy, but it is not
expected that we
deal with this at this
stage.
Activity 11
Teacher task
Key concepts
3
Work in groups1. Collect pictures from magazines & newspapers to show the different
types of energy.2. Make a poster on the wall of the classroom.3. Write sentences about the different types of energy, e.g waves have
movement & sound energy.
Making a class poster to show the differentforms of energy
What we want to assess What we expect from learners
Making a poster to show The poster must have:different forms of energy a a heading e.g. ‘Different Forms of
Energy’a pictures that illustrate different forms
of energy such as sound, heat, light, movement, electricity
a labels that name the form of energy next to each picture
Writing sentences about the The sentences must:different forms of energy a explain what form of energy is
shown in the picture, for example:– waves in the sea have movement
energy– the motor car has movement
energy– the iron uses electrical energy– the fire has heat energy
a the sentences must make sense
Learner task
4
Electrical energy travels throughdifferent materials
1. Give each group of learners a torch battery (electrical cell), a torchlight bulb, and two pieces of insulated electrical wire.
2. Ask learners to make the bulb light up using that apparatus. Check tosee that the learners can make a circuit that will light the bulb.
3. Introduce the word ‘circuit’ and show the learners how the electricitytravels around the circuit from one end of the battery along the wires,through the light bulb and back to the other side of the battery. Asklearners to show you with their fingers on their circuit. See supportmaterials about light bulbs (page 38).
4 After learners have made the circuit with a light bulb they test differentmaterials to see if they conduct electricity. They do this by making acircuit as shown below:
• Some materials conduct electricity – they are called conductors• Some materials do not conduct electricity – they are called
insulators• Electricity will only flow in a circuit made of materials that conduct
electricity
light bulb
cell
electricity flow
wire
5. Introduce and explain the words ‘conductor’ and ‘insulator’.Learners connect the material they want to test into the circuit with thelight bulb. If the light bulb shines, the material is a conductor (it letselectricity flow through it). If the light does not shine then the materialis an insulator (it does not let electricity flow through it).
6. Give the learners the materials to test as shown on the task card.
light bulb
cell
electricity flow
wirenail
Activity 22
Key concepts
Teacher task
5
Task card
Which materials can electricity flowthrough?
A.1. Use the apparatus to make the light bulb light up. 2. Draw a diagram to show how you made the light bulb light up.
3. Why did the bulb light up?
Because electricity went through the light bulb.
B.1. Now, make a circuit like this.
2. Does the light bulb light up?
Yes3. Did electricity flow through the circuit?
Yes4. Does the nail conduct electricity?
Yes
NOTE: Let the learnerscomplete Abefore youhand out B.
light bulb
cell
electricity flow
wire
Learner task Task card tophotocopy, page 28.
light bulb
cell
electricity flow
wirenail
6
Materials for Does the bulb light up? Did the material let Is the material testing Yes/no the electricity through? an insulator
Yes/no or a conductor?
nail yes yes conductor
paper clip (metal) yes yes conductor
metal coin yes yes conductor
wooden clothes peg no no insulator
plastic bottle top no no insulator
metal wire yes yes conductor
metal spoon yes yes conductor
plastic spoon no no insulator
a piece of glass no no insulator
a plastic button no no insulator
5. Now test some more things to see if they let the electricity flowthrough. Then record your results on the table:
Discuss with learners what happened when they tested different materials.
They should find that only metals are conductors while plastics, wood,stone and other non-metals are insulators.
Write a short report on what you did:
Today we tested materials to find out if they are conductors orinsulators.
We found out that nails, wires, metal cans, paper clips and metal
spoons conduct electricity. They are all made from metal. They are
all conductors. .
We also found out that clothes pegs, plastic bottle tops,
plastic spoons, plastic and glass do not conduct electricty.
They are insulators.
Teacher task
Learner task
Learner task
(continued)
What we want to assess What we expect from learners
A Using apparatus to make a circuit in which The learners must:a bulb lights up a successfully connect a light bulb into the
circuit so that it lights upa draw a diagram of the circuit showing the
following:
a explain that the light bulb lights up because it is connected into an unbroken circuit that allows electricity to flow through the bulb
B Testing different materials to find out if they The learners must:conduct electricity and writing a report a test the different objects made of different
materials by connecting them in a circuit with a light bulb
a correctly record their observations on the table as they are doing the test
a write a short report which correctly identifies those objects and materials that are insulators and those that are conductors of electricity, i.e. all metals conduct electricity, whilst wood, glass, paper, plastic and rubber are insulators
7
Electrical energy travels through differentmaterials
light bulb
cell
flow of electricity
wire
oh, i see. only metalthings conduct
electricity.
ActivityAAsssseessssmmeenntt 22
wire
paper clip
drawing pins
wire
wire
paper clip
drawing pins
wire
Switch in closed positionSwitch in open position
Making electric circuits to get light,sound, heat and movement energy
1. Provide learners with the following equipment to make electricalcircuits:– torch batteries– torch light bulbs– pieces of insulated copper wire– wire wool (steel wool)– small electric motors from old tape recorders and turntables– sucker sticks or wooden blocks– drawing pins– prestik– paper clips
2. Show learners how to make a switch using paper clips and wireattached to thick cardboard, a wooden stick or block. They will includea switch in each of the circuits that they make.
8
• We can get heat energy, light energy, sound energy and movement energy from electricity
• To get this energy from electricity we need to make an electrical circuit
• A switch is used to make and break a circuit • We can get electricity from a battery (an electrical cell)
Activity 33
Key concepts
Teacher task
9
Task card
Making electric circuits to get heat, light, soundand movement energy
1. Make three different electric circuits. Explain what happens whenyou close the switch.
CIRCUIT 1When I closed the switch
the light bulb lights up
CIRCUIT 2When I closed the switch
the motor starts
and the fan turns.
CIRCUIT 3When I closed the switch
the steelwool gets hot and melts.
Task card tophotocopy – page 30.
Learner task
10
1. Write a conclusion on the chalkboard with the help of the learners.
2. Help learners to understand that energy is stored in batteries and isreleased by a chemical reaction when the battery is connected into acircuit. Use the background information to help you – page 38–39.
3. The chemicals inside the battery store the energy. When we connectthe battery into a circuit the stored energy changes to electrical energyin the wires.
4. Assist learners to complete the following sentences.
Writing task Look at the circuits you made. Complete these summaries (energysequences) about your circuits.1. When you make a bulb light up stored energy in the battery changes
to electrical energy in the wires. This energy then changes to lightenergy in the light bulb.
2. When you start the motor and make the fan turn, stored energy in the battery changes to electrical energy in the wires. This electricalenergy then changes to movement and sound energy in the motorand fan.
3. When you heat up some steelwool stored energy in the batterychanges to electrical energy in the wires. This electrical energy thenchanges to heat energy in the steelwool.
CONCLUSION1. When I closed the switch, the electrical
energy flowed from the battery to thelight bulb and back to the battery. This iscalled an electrical circuit.
2. I can get heat, light, sound and movementenergy from electricity. The electricitycomes from the battery.
Teacher task
Learner task
11
What we want to assess What we expect from learners
Making electric circuits in order to get The learners must use the apparatus to makeheat, light, sound and movement energy. a a circuit which lights up a bulb
a a circuit which turns a fan and motor (the fan and motor will also make a sound)
a a circuit which heats a piece of steel wool
The learners must be able to manipulate the equipment with confidence
Drawing circuits and writing an explanation The drawings must show clearly: to say what happens when the switch a how all the components in the circuits are is closed connected to each other
a what happens when the circuit is connected,e.g. radiating lines around the light bulb that show it is shining
The sentences must say:a that the light bulb lights upa that the motor turns and rotates the fana that the steelwool gets hot
Completing summaries about the These are the completed summaries (sequences): sequence of energy flow a Stored energy in the battery changes to electrical
energy in the wires. The electrical energy then changes to light energy in the light bulb
a Stored energy in the battery changes to electrical energy in the wires. The electrical energy then changes to movement energy in the motor and fan
a Stored energy in the battery changes to electrical energy in the wires. The electrical energy then changes to heat energy in the steelwool
Making electric circuits in order to get heat,light, sound and movement energy
ActivityAAsssseessssmmeenntt 33
12
We also get heat, light, sound, andmovement energy from the mainelectricity supply
1. Bring a radio which can use the energy of batteries but which can alsorun off the main electricity supply. Also bring some electricalappliances which use energy from the main supply only.
2. Discuss with learners what they know about batteries and about themain supply. See background information on the batteries and themain supply on page 38–40.
Writing task
• We get electricity from a main electricity supply which comes to our homes from a power station
• The main electricity flows in a circuit from the power station to our house and into the appliances and back to the power station
• The electricity from the main supply is very powerful and can be dangerous. So it must be used correctly and carefully
Name of appliances What happens when I switch it on? What types of energy do we get from it?
Kettle the water gets hot and boils heat, sound and movement energy
Hair dryer (or heater) it makes a noise and gives out hot air heat, sound and . movement energy
Food mixer or fan the beaters or blades go round and it movement and sound makes a sound energy
Radio we can hear a sound sound energy
Lamp the light bulb lights up light and heat energy
Activity 44
Teacher task
Key concepts
Learner task
13
Complete these sentences:
1. When I switch on the kettle I get heat, movement and sound energy.
2. When I switch on a hairdryer/ heater I get heat, sound and movementenergy.
3. When I switch on a food mixer/fan I get movement and sound energy.
4. When I switch on a radio I get sound energy.
5. When I switch on a lamp I get light and heat energy.
We also get heat, light, sound, and movementenergy from the main supply
What we want to assess What we expect from learners
Completing sentences about The sentences should be completed as the energy we get when we follows:switch on appliances a when I switch on a kettle I get heat,
sound and movement energya when I switch on a hair dryer I get
heat, sound and movement energy. From a heater I get heat, movement and sound energy if it is a fan heater
a when I switch on a food mixer or fan I get sound and movement energy.
a when I switch on a radio I get soundenergy
a when I switch on a lamp I get lightenergy and heat energy
Learner task
ActivityAAsssseessssmmeenntt 44
14
How much electrical energy doappliances use from the main supply?
1. Collect pictures of electrical appliances. You will find these in thenewspapers especially towards the end of the month. Cut these out.
2. Hand out pictures to the learners and with the help of the learner taskcard, they must decide:– what is the main form of energy we get from each appliance?– how much energy (in Watts) does each appliance use?
3. Make a big chart on the chalkboard like this:
• We can get almost unlimited amounts of energy from the main supply
• Different appliances require different amounts of electrical energy to make them work
• We can tell how much energy an appliance needs by looking at the amount of electrical power it requires. The power is measured in Watts
• A Watt is how much electrical energy an appliance uses every second
Amount of energy used Light Sound Movement Heatevery second
10 Watt
100 Watt
250 Watt
500 Watt
750 Watt
1 000 Watt
2 000 Watt
3 000 Watt
ELECTRICAL APPLIANCES
Activity 55
Key concepts
Teacher task
15
it takes a lot ofenergy to make
things hot!
yes, but we don’t needmuch electrical energy to
get sound and light.
i wonder how muchenergy cell phones use?
Turn to page 16
4. Ask learners to place their pictures of appliances on the chalkboardto show the type of energy we get from it, and the amount ofelectricity it uses (in Watts).
Learner task Task card
How much electrical energy do appliances use from the mains supply?1. Place your picture on the class chart to show what energy you get
from your appliance and how much electricity it uses. Use the tablebelow to help you.
2. Look at the completed class chart and then answer these questions:a Which appliance uses the most energy? a Which appliance uses the least energy?
What we want to assess What we expect from learners
Answering the questions The answers must say:about how much electricity a that the most amount of electrical energy is used by appliances different appliances use such as: heaters, stove, kettles and hot plates
a that the least amount of electrical energy is used by radios, tape recorders, and clocks
a appliances that give us heat use the most energya appliances that give us light, movement and sound use the least
energy
16
The amount of energy appliances use
How much electrical energy do appliances use from the main supply?
3. Look at your chart again. Complete these sentences. Fill in the missingwords.
heat light sound movementa. Appliances use a lot of energy when they give us heat from electricity.b. Appliances use a little energy when they give us sound, light and
movement from electricity.
Learner task
ActivityAAsssseessssmmeenntt 55
Task card tophotocopy on
page 33.
17
Where does the main electricity comefrom?
With the help of the drawing below – ‘Where does the mains electricitycome from?’ – explain the following to the learners:The main electricity in our homes is produced in a power station.Wires connect the power station to our homes.When we plug in an appliance this brings the electricity from the powerstation to the wires in the appliance.When we switch on the appliance – this completes the circuit and allowsthe electricity to flow from the power station into the appliance and backagain.The electricity from the main supply is very powerful and can be verydangerous – so it must be used carefully and correctly.
• Main electricity is generated (produced) by power stations• The electricity travels in wires from the power station to our
homes and schools• When we want to use the electricity from the main supply we have
to connect the appliance by means of a 3-pin plug into the socket in the wall and switch on the electricity
• The 3-pin plug has three wires: the brown and blue wires connect to the main circuit, the yellow and green wire goes into the Earth and safely discharges dangerous electricity
Where does the main electricity come from?
power station
wall of house
The two wires (brown and blue) make a complete circuit from the power station to the house into the appliance andback – so that electricity can flow.
Steam
brown wire (live)
blue wire (neutral)
Earth wire (green/yellowl)
The Earth wire is buried in theground outside the house
The Earth wire takes excesselectrical energy safely intothe ground.
Activity 66
Key concepts
Teacher task
18
How do we use electricity safely?
1. Hand out the information about ‘Safety Inside the Home’ – page 37.2. Supply the learners with 3-pin plugs, electrical cord and screwdrivers
(use an appliance with its wires and plug. The learners can unscrewthe plug, then they can wire it correctly again.)
3. Hand out the questions about ‘Why are there three wires?’ Getlearners to discuss these questions in groups.
4. Introduce the idea of ‘Earthing’. Use the background information about‘Earthing’ to help you – page 40.
5. Introduce the terms ‘Electrical Shock’ and remind the learners aboutinsulators and conductors. Explain that although the wires in the cordare conductors they are encased in plastic insulating material whichprotects those using the appliances from being electrocuted (gettingan electric shock). Use the background information about electricalshocks to help you – page 40.
Task card
A. The 3-pin plug1. Wire up the 3-pin plug correctly like this:
2. Discuss the questions on the paper called ‘Why are there three wires?’3. Colour in the 3 wires in their proper colours.
• Most electrical appliances use energy from power stations• Many electrical appliances use a lot of energy and therefore it is
dangerous to use them incorrectly• An appliance must always be connected to the mains supply by
means of a 3-pin plug• The 3-pin plug must be correctly wired up to the appliance• Electrical wires are covered with insulating material to protect the
people using the appliance from being electrocuted (getting an electrical shock)
Task card tophotocopy on
page 34.
blue – neutral
green/yellow – Earth
brown – live
Activity 77
Key concepts
Teacher task
Learner task
19
Why are there three wires?
1. Facilitate a class discussion about why there are three wires in the 3-pin plug making sure that the learners can answer the questions.
2. Cut out the pictures and sentences from the safety information – page37, and put them into envelopes for the learners.
Task card
B Using electricity safely1. Look at the pictures of people doing dangerous things with electricity.
Discuss:a What is dangerous in each picture?a What will happen to you if you do these dangerous things withelectricity?
2. Match each picture with the correct sentence and then put thesentences back into the envelope again.
3. Now write your own safety rules for when you use electricity.
don’t do don’t
Task card tophotocopy on
page 35.
Leerdertaak
Learner task
(continued)
Do not insert bare wiresinto electrical sockets
Always use a correct plug.To remove – or insert:switch off first and holdonto the plug.
Do not use damaged cords– replace immediately
• The blue wire is calledthe Neutral wire.
• Another name for the green/yellowwire is the Earth wire
• If the green/yellow wire comesloose then there will be noconnection to the safety wire thatgoes into the ground. This takesexcess current to the Earth if theappliance is faulty.
• The wires are coated in plastic toinsulate them so that we are protectedfrom the dangerous electrical energy.
• If the brown orblue wire comesloose, then thiswill break thecircuit. Theelectrical currentwill not be able torun in the wires.The appliance willnot work becauseit will have noelectricity supply.
• The cover is made fromplastic to insulate the wireand protect us from thedangerous electricalcurrent. Inside the plasticare three wires – the Livewire, the Neutral wire andthe Earth wire.
• Another name forthe brown wire isthe Live wire.
20
1. Make sure that my hands are dry before I touch any electrical plugs.2. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
4. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
5. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
6. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
7. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Rules for using electricity safely at home When I want to use electricity safely I must:task
Learner task
(continued)
4. Finally draw a picture of an electrician working. Remembereverything you have learned about using electricity safely.
What we want to assess What we expect from learners
Wiring up a 3-pin plug The learners must:a use the screwdriver confidently to wire up the pluga attach the wires securelya attach the green/yellow Earth wire to the earth pin, the blue wire
to the neutral pin and the brown wire to the live pin
Answering questions about The learners must show they understand that:the reason why there are a the brown live wire and the blue neutral wire become connectedthree wires into the circuit from the power station when we switch on the
appliance. If one of these wires comes loose there is no longer a complete circuit and the electricity stops flowing
a a large amount of electrical energy flows through the live wirea the green/yellow earth-wire becomes connected to a wire that
goes into the ground when we switch on the appliance.a the Earth wire is there to protect people from getting electric
shocks. If it becomes disconnected then there is no safe connection from the appliance to the ground. This is dangerous if the appliance develops a fault
a the electrical wires are made from copper, a metal that conducts electricity very well
a the wires are covered with plastic that does not conduct electricity to prevent electricity escaping and causing shocks
Writing their own safety The learners must be able to:rules for using electricity a identify dangerous ways of working with electricity, e.g. putting
bare wires into a plug socketa say what they think will happen to them if they use electricity in
dangerous waysa write a set of safety rules to warn people about the dangers
they have identified
Drawing a picture of an The drawing must show:electrician working a the electrician wearing appropriate dress e.g. a uniform, wearing
shoes with thick soles, wearing rubber gloves, etca appropriate tools used by an electrician, e.g. a ladder to reach
the power lines, a screwdriver, etca doing some kind of work that an electrician might do, e.g. fixing
a plug, laying electrical cables in the road, etc
21
How do we use electricity safely?Activity
AAsssseessssmmeenntt 77
22
PERIOD 1Activity 1
• Learners collect pictures ofdifferent types of energyand make a poster on theclassroom wall. (50 min)
PERIOD 2Activity 1 (cont.)
• Learners write sentencesabout the different types ofenergy.
PERIOD 3Activity 2
• Learners make a circuit tomake a bulb light up. (10 min)
• Learners test differentmaterials to see if they areinsulators or conductors ofelectricity. (40 min)
PERIOD 4Activity 2 (cont.)
• Learners and teacherdiscuss the results of theinvestigation aboutconductors and insulators.(20 min)
• Learners write a shortreport. (20 min)
PERIOD 5Activity 3
• Learners make switchesand electrical circuits toget heat, light andmovement. (35 min)
• Learners write a shortconclusion. (15 min)
PERIOD 6Activity 3 (cont.)
• Teacher and learnerdiscussion about batteriesand how they work. (20 min)
• Learners write summariesabout the circuits theymade. (20 min)
PERIOD 7Activity 4
• Teacher introduces a radiothat uses batteries andmains electricity. (10 min)
• Learners recordobservations about energyand different appliances.(35 min)
PERIOD 8Activity 4 (cont.)
• Learners completesentences about energyand appliances. (15 min)
• Teacher helps learners tocorrect their sentences.(20 min)
PERIOD 9Activity 5
• Learners sort and displaypictures of differentappliances according tohow much electricity theappliances use and whatform of energy they supply.(40 min)
PERIOD 10Activity 5 (cont.)
• Learners write to answerquestions about the classdisplay. (15 min)
Activity 6
• Teacher explains howelectricity gets from thepower station to anappliance in our homes(using the diagram of themains supply). (30 min)
PERIOD 11Activity 7
• Learners wire up three pinplugs. (50 min)
PERIOD 12Activity 7 (cont.)
• Learners discuss thequestions about why thereare three wires.(20 min)
• Teacher and learnersdiscuss the importance ofhaving live, neutral andearthing wires in a plug.(20 min)
Suggested work scheme for the grade 5 learning programme
ENERGY AND CHANGE
PERIOD 13Activity 7 (cont.)
• Learners match pictures ofpeople using electricitydangerously with theircorrect sentences. (30 min)
• Learners begin to writetheir own electricity safetyrules. (15 min)
PERIOD 14Activity 7 (cont.)
• Learners complete thewriting of their safety rules.(30 min)
• Learners draw a picture ofan electrician working,taking into accounteverything they have learntabout electricity. (20 min)
Total time for this Learning Programme = 14periods @ 50 min per period = 11,6 hrs. This isthree weeks’ work. (Recommended for NaturalSciences and Technology = 4 hrs per week)
28
light bulb
cell
electricity flow
wirenail
TASK CARDSPhotocopy for learners
Activity 2
Which materials can electricity flow through?
A1. Use the apparatus to make the light bulb light up.2. Draw a diagram to show how you made the light bulb light up.
diagram
3. Why did the bulb light up? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B 1. Now make a circuit like this.
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2. Does the light bulb light up?
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3. Did electricity flow through the circuit?
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4. Does the nail conduct electricity?
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5. Now test some more things to see if they let the electricity flow through.
Record your results on the table:
Materials for Does the bulb light up? Did the material let Is the material testing Yes/no the electricity through? an insulator
Yes/no or a conductor?
nail
paper clip (metal)
metal coin
wooden clothes peg
plastic bottle top
metal wire
metal spoon
plastic spoon
a piece of glass
a plastic button
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Task card
Activity 3
Making electric circuits to get heat, light, sound and movement energy
1. Make three different electric circuits. Explain what happens when you close the switch.
CIRCUIT 1
When I closed the switch . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CIRCUIT 2
When I closed the switch
. . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CIRCUIT 3
When I closed the switch
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Name of What happens when What types of energy appliances I switch it on? do we get from it?
Kettle
Hair dryer (or heater)
Food mixer (or fan)
Radio
Lamp
Task card
Activity 4
Light, sound, movement and heat energy
1. Plug in some electrical appliances and switch them on.2. Record what happens:
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Task card
Activity 5
How much electrical energy do appliances use from the main supply?
1. Place your picture on the class chart to show what energy you get from your appliance andhow much electricity it uses. Use the table on the opposite page to help you.
2. Look at the completed class chart and then answer these questions:a Which appliance uses the most energy? a Which appliance uses the least energy?
3. Look at your chart again. Complete these sentences. Fill in the missing words.
heat light sound movement
a. Appliances use a lot of energy when they give us ——————————————— from electricity.
b. Appliances use a little energy when they give us ———————————————from electricity.
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APPLIANCEAmount of electrical energy it uses in watts
cell phone 3 W
radio/tape/CD player 15 W
fluorescent light 40 W
table lamp 60 W
sewing machine 75 W
fridge 150 W
fax machine 170 W
microwave oven 230 W
colour TV 340 Welectric drill 360 W
hair dryer 450 W
washing machine 500 W
vacuum cleaner 700 W
iron 720 W
toaster 1 000 W
electric frying pan 2 000 W
kettle 3 000 W
heater 3000 W
hot water cylinder 4 000 W
stove 8 000 W
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Activity 7
Task card A The 3-pin plug
1. Wire up the 3-pin plug correctly like this:
2. Discuss the questions on the paper called ‘Why are there three wires?’
3. Colour in the three wires in their proper colours
Why are there three wires?
What is the green/yellow wire for?
What is the blue wire for?
What is the brown wire for?
• Give another namefor the brown wire.
• Give another namefor the blue wire.
• Give another name forthe green/yellow wire.
• What happens if thegreen/ yellow wirecomes loose?
• Why are the wirescoated in plastic?
• What happens ifthe brown or bluewire comesloose?
• Why is the cover madefrom plastic?
What is inside the plastic?
blue – neutral
green/yellow – Earth
brown – live
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Activity 7
Task card B
Using electricity safely in the home1. Look at the pictures of people doing dangerous things with electricity.
Discuss:a What is dangerous in each picture?a What will happen to you if you do these dangerous things with electricity?
2. Match each picture with the correct sentence and then put the sentences back into theenvelope again.
3. Now write your own safety rules for when you use electricity.
Rules for using electricity safely at home
When I want to use electricity safely I must – e.g.
1. Make sure that my hands are dry before I touch any electrical plugs.
2. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -3. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -4. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -5. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -6. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -7. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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a electrician working
Task card B4. Finally draw a picture of an electrician working. Remember
everything you have learned about using electricity safely.
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SAFETY IN THE HOMEBe safe and happy with electricity by observing these simple rules.
Always wire yourplug correctly.
Do not use a damaged cord.Replace it immediately
Yellow/Green – Earth Brown – live Blue – neutral
Do not pull the plug by the cord.Switch it off first and remove byholding the plug.
Do not insert bare wires into electricalsockets. Always use a correct plug.
Do not overload a socket. Use a multiplug.
Never stick your fingers into a socket.Use a safety plug.
Never run an extension cord under a carpetor where people will walk or trip over it.Run the cord alongside the wall.
Never use electricity near water.Water and electricity do not mix.
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This is what a light bulb looks like inside.
glass bulb
tungsten filament
metal casing
plastic pin
metal pin
Teacher supportHow a light bulb worksA light bulb will light up when there is a
pathway for electricity to flow through it.
The electricity must flow from the one
end (pole) of the battery through the
electric wires, then through the filament
(thin wire) inside the light bulb and then
back to the other end (pole) of the battery.
When you connect a light bulb you must
make sure that there is one connection to
the metal pin at the bottom of the bulb
and another to the side metal casing
around the base of the bulb.
Electricity will always choose the
shortest and easiest pathway along
conductors. If the easiest route does not go
through the filament the bulb will not light
up.
Background information about batteries (cells)A torch battery is also sometimes called an electric cell. (Scientists use the
term ‘battery’ for a number of cells.) The most common battery that we
use is a dry cell battery, which has chemicals sealed inside a casing.
The chemicals inside react together. This chemical reaction produces
electricity, which can be used when the battery is connected into a circuit.
When its chemicals have finished reacting, it stops working and cannot
be recharged.
We use very small dry cell batteries to power digital watches and
pocket calculators. These have other chemicals inside them.
Other batteries can be recharged with electricity and used again such
as a cell (battery) for lap top computers. The car battery is made up of
several lead-acid cells and these can be recharged.
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Batteries and cells
Mercury battery
This type of battery is used for poweringdigital watches and pocket calculators. It is amercury battery.
An electrolyte is a liquid or moist substancewhich conducts electricity e.g. lemon juice,salt water, ammonium chloride paste.
Dry cell battery
The common dry cell batteryproduces a voltage of 1.5volts. The zinc forms thebattery casing. The electrolyteis ammonium chloride in theform of a moist paste.
Lead acid battery
The lead acid battery is used in cars. It is socalled because it has electrodes that are madeof lead, and the electrolyte is sulphuric acid.The battery consists of six sets of cells, whichproduce two volts each, for a total of 12 volts.
nickel-plated case
electrolyte
zinx powder
mercuric oxide and graphite
carbon rod (positive)
ammonium chloride paste
terminal
terminal
top-up cover
cell
casing
lead plates
positive plate
negative plate
zinc case (negative)
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BACKGROUND INFORMATION ABOUT EARTHINGMost houses, that have an electricity supply from the power station (main supply),
have a wire from the electricity board which goes through the wall and is buried in
the ground nearby. This is called an earthing wire. This is for the safety of those who
are using the electricity inside the house. When an appliance is faulty it can take
more electricity than it should. A faulty appliance is dangerous because when
somebody touching it can get burned or electrocuted. The earth wire conducts the
excess electricity in the faulty appliance down the wire into the ground where it
becomes harmless so that it will not cause a fire in the appliance or electrocute
somebody.
People’s bodies can conduct electricity. Without an earth wire the excess
electricity from a faulty appliance would flow through the person into the ground.
The person would get an electrical shock, or burns or even die from these. If there is
an earth wire, then the electricity will run through it as it is a better conductor than
a human body.
Many appliances are made of metal and use a lot of electrical energy. They must
have an earth wire. Other appliances are made of plastic (even some kettles and
irons) and do not draw a lot of electricity. They do not need an earth wire because
they are made of insulating material (plastic). If a plastic appliance is faulty, the
electricity can’t easily flow through the plastic to the person and electrocute
him/her.
BACKGROUND INFORMATION ABOUT ELECTRIC SHOCKSWhen a large amount of electrical energy passes through someone’s body we say
s/he has suffered an electrical shock or has been electrocuted.
The person usually falls down, sometimes s/he stops breathing for a short while,
and may suffer severe burns or he may be killed.
When a person has been electrocuted, the first thing to do is to switch off the
electricity at the main switch before you touch him / her to give help.
If the electricity has not been switched off and the electrocuted person is still in
contact with the electricity you could also be electrocuted when you touch him/her.