Download It`s Electrifying manual_Updated March2012

IT’S
ELECTRIFYING!
A Facilitator's Guide to Electricity
It’s Electrifying!
Developed by Gillian Gerhard and Angelica Workman for Let’s Talk Science
© 2002-2011 Let’s Talk Science
Let’s Talk Science is an award-winning, national, charitable, science outreach organization. We
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A. Description of Workshop
Overview of Workshop
Grade for Workshop/
Appropriate Age
This activity is
designed for use in
Grade 4-6 classrooms
or with children ages 9
to 12.
Science Topics





Electricity
Magnetism
Parallel and
Series
Circuits
Conductors
and Insulators
Energy
Sources
 Testing
Materials
 Structural
Strength
Do electrons come out of both ends
of a battery? Why won’t the bulb
light? What’s a parallel circuit? Is
wood a good conductor or an
insulator? Students will explore
these questions and more through
fun, hands-on stations.
Overall Objectives
 To familiarize students
with a circuit.
 To demonstrate series and
parallel circuits and
discuss the differences.
 To learn about insulators
and conductors
 To discover how
electromagnets work.
B. How to Run This Workshop
Physical Requirements
You will need a large classroom with a clear space big enough for all students to sit
in a circle. You may need to set up stations.
Materials and Set-Up
Note: For more detail, see Kit List
Activity #1 –
Circuit Design
Chicken
Demonstration
12-15 zip-bags
containing:
*1, 1.5V C Cell
2 chirping
chickens
“Load and
Source” signs
“Electricity”
signs
6” coated
copper wire
stripped at
each end
*1 bulb
*It’s
Electrifying
Data Sheet
(these get used
up every
workshop)
2 bean bags or
tennis balls or
ping pong balls
(electrons)
Activity #2 –
Insulators and
Conductors
4 zip-bags containing:
Activity #3 – Parallel
and Series Circuits
Activity #4 Electromagnet
4 zip-bags containing:
3 wires with alligator
clips on each end
*1 bulb with holder
6 wires with alligator
clips on each end
*2 bulbs and holders
4 zip-bags
containing:
*4, 1.5V D Cells
*1, 1.5V C Cell with
holder
*1, 1.5V C Cells with
holders
1 m insulated
wire with ends
stripped
2 of each of following
supplies: shoelaces,
string, plastic ruler,
metal ruler, wooden
ruler, empty plastic
cup (air), pipe
cleaner, bendy straw,
aluminium foil, pencil,
balloon
Insulators and
Conductors Task
Card
Troubleshooting Card
*Blank paper and
pencils
20 + paper clips
Parallel and Series
Circuit Task Card
2 pairs of
scissors
Troubleshooting Card
*Electrical tape
or masking tape
Electromagnets
Task Card
Extra blank paper for
testing objects from
around the class
(optional)
1 galvanized nail
*Consumable items (eventually – not after every workshop)
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DELIVERY HINT: You can use the same zip-bags filled
with materials for Activity #2 and Activity #3 if you are
not setting up stations. You may just have to increase the
number of zip-bags that you use.
Timing of Activity
Part of Workshop:
General Introduction
Activity #1
Chicken Demonstration
Activity #2
Activity #3
Activity #4
Wrap-Up
Suggested Timing:
5 min.
30 min.
15 min.
15 min.
15 min.
15 min.
10 min.
Cumulative Timing:
5 min.
35 min.
50 min.
65 min.
80 min.
95 min.
(OPTIONAL)
105 min.
C. Introduction to Topic
CHOICE: You can briefly ask the students what electricity
is, why it’s important to us and where we get it from to
start the workshop OR you can move right into Activity #1.
D. Activities
CHOICE: There are 4 activities and 1 demonstration for you
to choose from. At lower grade levels (Gr. 4), leave out
Activity #4 (Electromagnets) unless the class is very advanced.
At higher grade levels, you will want to set up stations; at
lower grade levels, you can go through the activities together.
You choose the order of activities and where you fit in the
demonstration.
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ACTIVITY #1: CIRCUIT DESIGN (30 min.)
It’s Electrifying Datasheets
Objective of Activity
 To introduce circuits.
 To introduce the components of a circuit.
Suggested Instructions, Q & A
(Hand out worksheets and zip-bags ahead of time.)
Some of you will already have discovered the worksheets and zip-bag on your desk.
Working in groups of 2-3, see if you can come up with a way to make the light bulb
light up using just the materials in the bag. You’ve got about 5 minutes, and in that
time I would like you to draw on your worksheet a picture of how you’ve arranged
the materials. Don’t worry if it doesn’t work the first time – we can learn as much
from what doesn’t work as from what does.
If you find an arrangement that makes the bulb light, draw the picture in the “bulb
lights” box, and if you find an arrangement that doesn’t make the bulb light, draw
that picture in the “bulb didn’t light” box.
(This is your prior knowledge activity. Give the students 5 minutes depending on
their level of prior experience with electricity and circuits. This should become
obvious while watching them experiment. Stop them once a few groups have been
successful – it’s not necessary for them to all have been successful. Encourage
students who find one way to make the bulb light to find a different arrangement
that also works. Encourage students who didn’t get the bulb to light to draw a
picture of their circuit.)
(Collect the bags of materials, retaining one for demonstrations.)
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Discussion
Did anyone get the bulb to light? Can someone volunteer to show us how you lit the
bulb?
Let's draw this on the board (all possible arrangements shown below.)
+
+
-
-
+
+
-
Did anyone discover a way to put the circuit together so that the bulb didn’t light?
Can someone volunteer to show us how?
Let's draw that on the board (possible arrangement shown below.)
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Did anyone have a different arrangement to light the bulb? Did you make a picture
of it on your sheet? How about a different way to not light the bulb?
So there is more than one way to make a circuit.
Let’s take a look at our two “circuit” drawings here. We’re going to examine at
least 4 elements of our drawings.
1)
SOURCE
Battery
(Draw a (1) on top of the cell in the “working” picture)
Why do we need the battery? What does it do?
It provides energy, power, electricity source.
What kind of energy?
Electricity.
What is electricity?
Current, stuff that runs lights and appliances, electrons and protons, charged
particles, energy.
Electricity is a form of energy consisting of charged particles. We generally think
of the negatively charged particles or electrons. The electricity in our circuit here
is current electricity, which means it’s moving. The electrons released by a
chemical process in the battery flow, or move. That movement of electrons is the
electricity.
Where does electricity come from?
Batteries, the wall, power plants (generated by: water, coal, nuclear energy,
wind, gas, solar energy)
So we need an energy SOURCE. (Write Source next to the cell)
In this case it’s our battery.
2)
CONDUCTOR
Wire
(Draw a (2) beside the wire on the “working” picture)
What does the wire do? Why do we need the wire?
It provides a medium in which the electrons can moves. It conducts the
electricity.
It moves the electricity from the source.
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So we also need a CONDUCTOR for the energy. (Write CONDUCTOR on the
board)
Are wires the only things that will move electricity? Will it flow through anything
else?
Yes/No/Maybe
What else could we use?
Paperclip, wood, water
Why does it flow through wires? What makes something a good conductor?
They are made of: metal, steel, copper.
What is special about metal? Why does it conduct electricity? What properties
does it possess that make this possible?
They can easily take electrons because their inner bits (their atoms) have
room for electrons. BUT metals do NOT hold onto electrons very well, they
don't like to keep them. When you pump electrons in, metal atoms give them
away to each other...causing a FLOW of electrons through the metal (Just
like Hot Potato – something that conducts electricity well plays the hot-potato
game with electrons well. Taking them and passing them along quickly.)
What is the opposite of conducting? If conductors take electrons and pass them
on, then what would the OPPOSITE of a conductor do?
They might take electrons and not pass them on or just not take the electrons
at all.
This is called an insulator.
What do you think a good description of an insulator would be?
Insulators do not have room in their atoms for extra electrons so they don't
want to take any new ones on. BUT sometimes they do accept electrons, when
this happens they hold onto to them very tightly, not wanting to give them
away. Electrons do NOT flow easily through insulators. (For the hot potato
analogy, an insulator might have its hands full so it can’t take the potato.)
Give me some examples of materials that conduct electricity.
Metal
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Give me some examples of insulators.
Plastic, rubber, fibre glass insulation, glass
One of the activities you will do during today's session is to test your hypotheses
about which materials conduct electricity and which materials insulate.
So, we’ve got a source and a conductor. What happens if there is no light bulb?
Alone, the flow of electricity through a wire just produces a hot wire and a worn
out battery. We want to make use of that flowing electron phenomenon to do
something.
Can you think of anything useful that uses electricity?
lights, computers, toaster, radio, ….
So, back to our circuit, we need a load - something that uses the electricity.
That’s where the light bulb comes in.
3)
LOAD
Light bulb
(Draw a (3) beside the light bulb on the “working”
picture)
Does anyone know how the light bulb uses the flow of electrons?
The electrons flow into the side of the bulb, through the filament and out the
bottom into the positive terminal of the battery.
Why does the filament glow when electrons go through it?
The filament is not a good conductor. It has many imperfections that cause
resistance to the movement of the electrons. This increases COLLISIONS,
producing heat. The heat makes the filament glow.
The other diagram (of a set up that did not light the bulb) has all 3 critical parts.
Why didn’t the bulb light?
Need another wire, need to connect them
What would you do with the other wire, how would you connect them? Does
someone want to come up and draw it?
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(Make sure one wire connects to the side of the bulb and another at the very tip of
the bulb)
We need to make a closed circle. That’s the fourth critical part of our circuit.
4)
CIRCUIT
What do I mean by a circuit?
The drawing, the arrangement.
A circuit actually refers to a closed loop around which electrons can flow. It
has to be present for everything to work. If it isn’t closed, the electrons
won’t flow … no electricity (= open circuit!)
Does anyone know which way the electrons are flowing around this circuit?
positive to negative, negative to positive, both ways, …
ELECTRONS WILL ONLY FLOW FROM NEGATIVE TO POSITIVE!!!
Who has heard the rule: Opposites attract?
What does it mean in magnets?
North is attracted to South
In electricity we talk about positive and negative charges. Electrons are
NEGATIVELY charged. They want to move to the positive terminal of the battery.
SO...they flow out the negative end, around a circuit and into the positive end.
BUT only if it senses the positive "pull". It won't move unless it is attracted by
the positive. That means the circuit needs to be closed.
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CHICKEN DEMONSTRATION (15 min.)
Use Signs – Electricity, Load, Cell
Suggested Instructions, Q & A
We are going to be a circuit, and this is going to require cooperation. Form a tight
circle sitting or standing in an open area in the classroom.
DELIVERY HINT: This works best if the children are
not sitting on a rug and no one is touching metal.
What are the four parts that we need? (Hand out cards)
1. A source, a dry cell. (one student will be the ‘cell’)
2. Wire, a conductor (most students sitting in the circle are ‘wires’)
3. A load, an electrical appliance (like a CD player or school bell) (one student
will be the ‘load’ and will have to make a noise whenever they receive an
electron, and stop when they don’t have an electron in hand.)
4. A closed circuit. (the circuit is closed if all the students’ ‘wires’ (knees) are
touching. The ‘cell’ needs to make sure this is happening before sending out an
electron, and one ‘wire’ cannot pass an electron to another if the circuit isn’t
closed.)
There are some interesting things about ‘wires’ – they’re really quiet! And ‘loads’
don’t work unless they have electrons flowing through them. So, ‘loads’, you
shouldn’t be making any noise unless you have electrons.
(Hand out two ‘electrons’ to the ‘cell’. The ‘cell’ will start the flow of ‘electrons’
around the closed circuit. Remind students that the electrons must start and end
at the ‘source’. Remind ‘source’ that the electrons won’t flow unless the circuit is
closed – they need to confirm this. Remind students that the ‘wires’ are
conductors – like the hot potato game. Take the ‘electron’ and pass it along. When
the ‘load’ gets the electron he/she should make a sound, and stop when they give
the ‘electron’ away. Let the ‘electrons’ go around the circuit once or twice.)
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(Watch for teachable moments here – breaks in the circuit (electron flow should
stop), electrons flowing out of both hands of the ‘cell’ (positive and negative),
students noticing that their load only makes beep-beep sounds not continuous
noise, but their CD player makes continuous sound – this is because real electrons
move at close to the speed of light. You can try adding more ‘electrons’ in to the
circuit to make the sound more continuous.)
(Once they get the concepts, remove the ‘electrons’ and the component cards and
introduce the chicken. )
I’ve got a little chicken here that contains both the source and the load in the
same fuzzy yellow box. Let’s replace our ‘cell’ and electrical devices with this
chicken and see if we really can be conductors.
The chickens are Easter toys that contain a battery and a chirping mechanism.
When we touch both of the terminals on the bottom of the chicken, a circuit is
completed and the chicken starts to chirp. When we stop touching one or both of
the terminals, the chicken stops chirping.
(Students hold hands and one at each end of the circle connects to the chicken
terminal. Watch what happens when one person breaks contact.)
DELIVERY HINT: Students cannot be touching anywhere else
(i.e. at the knees) or anything else (i.e. desks) for this to
work. Also, if girls and boys are making a fuss about holding
hands, they can touch pinkies instead.
Let’s introduce a second chicken into our circuit (again with its own cell and load.)
(Have students next to the first chicken connect to the second chicken terminals.)
Notice that I’ve put these two chickens into our circuit IN SERIES - that is one
after another.
What happens if we break the connection at one of the chickens? Does the other
keep chirping? Why not? (see  on diagram)
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The chickens stop chirping because the circuit is broken – the electrons can’t
get back to their own positive terminal.
(Draw a diagram of this circuit on the board.)
Can anyone think of a way we could rearrange this human/chicken circuit so that if
we broke the connection at the first chicken, the second would keep on chirping?
(Move some of the students, including the second chicken, into or outside of the
circle. Close the original circle and check that the first chicken chirps. Have the
students near the second chicken form a wire running parallel to the first chicken
and tap into the circle.)
Notice that we’ve now put these two chickens IN PARALLEL to one another (like
lights in this classroom – if one goes out, they don’t all go out), that is one beside
the other, each with their own wires running to the circle. Both chickens should
chirp.
What are the electrons doing in this circuit?
Since both chickens are the same, some of the electrons are going through
chicken one and others through chicken two.
(See what happens when you break the connection at the first chicken but between
the “tap into the circle” people from the second chicken.) (see  on diagram)
Chickens
2
2
1

1

Break Here
Series

Parallel
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Chicken two should keep on chirping, but chicken one should stop.
What are the electrons doing now? Where are they going?
See what happens when you break the circuit outside of the “tap into the circuit”
people) (see  on diagram)
Chicken one should chirp, but chicken two should not.
(Draw a diagram of this circuit.)
(See what happens if you take chicken two completely out of the parallel circuit,
but leave the people/wire there with a gap where chicken two was.)
Chicken one should keep chirping.
(Have students go back to their desks.)
ACTIVITY #2: INSULATORS AND CONDUCTORS (15 min.)
Use Insulators and Conductors Task Card
Objective of Activity
 To test various materials to determine whether they are insulators or
conductors of electricity.
Suggested Instructions, Q & A
(Go over Task Card instructions with entire group. Point out where they should fill
in information on the Data Sheet. Remind them that there may be a
Troubleshooting Card at the activity – read it if they have problems!)
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ACTIVITY #3: PARALLEL AND SERIES CIRCUITS
Use Parallel and Series Circuit Task Cards
Objective of Activity
 To design parallel and series circuits and learn the difference between the
two.
Suggested Instructions, Q & A
(Go over Task Card instructions with entire group. Point out where they should fill
in information on the Data Sheet. Remind them that there may be a
Troubleshooting Card at the activity – read it if they have problems!)
ACTIVITY #4: ELECTROMAGNETS
Use Electromagnets Task Card
Objective of Activity
 To create an electromagnet and manipulate the strength of the magnet by
changing the number of coils and/or the number of batteries used.
Suggested Instructions, Q & A
(Go over Task Card instructions with entire group. Point out where they should fill
in information on the Data Sheet. )
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E. Wrap-Up
When you tested the insulators and conductors, did anyone find any surprises?
Was there anything you thought would conduct and didn’t? Anything that you
thought would insulate that conducted?
When you were making your parallel and series cirucits, did anyone get both bulbs
to light? Get your series circuit to work? Did you draw it? How about the parallel
series? Did you draw it?
(The students can draw their circuits on the board. Make sure everyone uses the
same symbols to represent source, load, conductor… )
Did anyone magnetize their nail? Did you make your electromagnet stronger?
How? Does anyone have ideas about how it works?
The current flowing through the wire induces a magnetic field in the metal nail –
lining up its poles and turning it into a temporary magnet. Magnetic fields develop
perpendicular to electric fields, so we wrap the wire around the nail to get the
current flowing around the nail and the magnetic field aligned along the nail. That
field is only present as long as the current is flowing. You can make the field
stronger by increasing the amount of current. We do this either by increasing the
amount of coils (sort of like increasing the electric surface area) or by increasing
the amount of current going through those coils (by adding more batteries.)




What was your favourite activity today?
Do you think Science is fun?
Do you like Science?
Do you have any questions for me?
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F. Glossary
Ammeter
An instrument used to measure the amount of electric current flowing through a
particular point in an electrical circuit.
Battery
One or more cells in series.
Cell
An electrochemical device that converts chemical energy into electrical energy.
Circuit
The complete path of an electric current. An open circuit does not allow current to
flow, a closed circuit does.
Conductor
A material through which electrons can flow.
Electric Current
A flow of electric charge through a conductor.
Electricity
A form of energy, consisting of oppositely charged particles, that can produce
light, heat, magnetism and chemical change; and which can be generated by
friction, induction or chemical change.
Electromagnet
A temporary magnet produced by an electric field.
Electrons
These are negatively charged particles found orbiting the nucleus of an atom.
Since electrons are negatively charged, they are attracted to positive charges and
flow from negative to positive.
Insulator
A material which allows no electrons (or very few) to pass through.
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Parallel Circuit
A circuit that is formed when the components are arranged so that there is more
than one path for the current to take.
like terminals
+
_
_
Resistance
Is caused by structural "imperfections" in a material that cause electrons to
collide with them; it slows down the flow of charges.
Series Circuit
A circuit that is formed when the components are arranged so that there is a
single path for the current to take.
+
_
Voltmeter
An instrument used to measure the potential difference between any two points in
an electrical circuit.
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G. Suggested Resources
Websites
What is Static Electricity?
http://www.sciencemadesimple.com/static.html
The Minds that Discovered Electricity
http://www.outlawnet.com/~oclass/electricity/founders.html
Canada Science and Technology Museum
http://www.science-tech.nmstc.ca/english/schoolzone/Info_Electricity.cfm
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