Exploring Electricity
Subject Area
Physical Science
Grade Level
4th – 8th
Length of Lesson
4 -7 (50 minute periods)
Standards: (Indiana State Science Standards)
4.2.3 Make simple and safe electrical connections with various plugs, sockets,
and terminals.
4.3.16 Investigate and describe that without touching them, material that has been
electrically charged pulls all other materials and may either push or pull
other charged material.
6.3.23 Explain that electrical circuits provide a means of transferring electrical
energy from sources such as generators to devices in which heat, light,
sound, and chemical changes are produced.
8.3.19 Investigate and compare series and parallel circuits
Related Standards:
7.3.15 Describe how electrical energy can be produced from a variety of energy
sources and can be transformed into almost any other form of energy, such
as light or heat.
8.3.19 Compare the differences in power consumption in different electrical
devices.
Things to think about:
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
The first two activities dealing with the effects of the buildup of static charge
should be done on dry days. If the air in the classroom is too humid the
activities may simply not work! The water molecules in the air will constantly
pick up the charges (electrons) and carry them away. With this happening it is
difficult to build up the needed amount of charge to perform the experiments.
This unit starts from square one assuming no basic knowledge of electricity or
circuits. Even though the activities are designed to conceptually build on one
another, feel free to pick and choose, omitting activities which cover content
already understood by your students.
Author: Aaron Debbink
Activity #1
Fun with the Van de Graph Generator
Description: These series of demonstrations engage the curiosity of the students and
introduce the students to some common experiences with the behavior of electrical
charges. It’s also just plain fun!!
4.3.16 Investigate and describe that without touching them, material that has been
electrically charged pulls all other materials and may either push or pull
other charged material.
1. Have the Van de Graph generator setup
when the students enter the room with
the paper strips taped evenly around the
sphere. For effect you can place caution
tape around the generator to create an air
of danger. However, this could
discourage some students from wanting
to volunteer to experiment with the Van
de Graph generator later in the activity.
2. Turn on the Van de Graph generator so
that the paper strips stand straight up.
Now turn the generator off and discharge
the sphere with the discharger. If you do
not have a discharger simply discharge the
metal sphere by touching it. Ask the
students to observe what happens to the paper strips after the sphere is
discharged. Ask them to think about the following questions without giving any
answers to the questions:
a. What causes the spark that you see? Electrons are jumping through the air
from the generator to the discharger.
b. What do you think causes the paper strips to fall down? The paper strips
will fall down when a spark jumps through the air, this happens because at that
instant electrons are leaving the surface of the sphere and the paper strips on it.
The presence of the electrons on the paper strips repelling one another causes them
to stand up, so if there are now less electrons, the paper strips will no longer stand
up.
3. Next, with the generator off, place ten aluminum pie plates upside-down on top
of the generator. Turn on the generator and watch the pie plates successively
float off of the generator.
4. Light a fluorescent bulb with the Van de Graph generator. While standing on a
small wooden stool or ladder place the prongs of the bulb on the sphere. You
can change the amount of lighted gas by moving your hand up and down the
bulb, or you can simply grab the light near one end and let an arc jump to the
middle of the tube to make the bulb light up.
5. (Optional) Turn of the Van de Graph generator and ask a willing student to come
up and place his/her hand on the sphere. Now turn on the generator and watch
the student’s hair stand on end (thin, straight longer hair works the best for this
demonstration!).
Activity #2
Static Stations
Description: This is an exploration of the effects that charged objects can have on one
another and non-charged objects. An explanation is given about what the students are
doing when they charge things. With this knowledge they investigate the effects of
charge on other charged objects and objects without charge.
4.3.16 Investigate and describe that without touching them, material that has been
electrically charged pulls all other materials and may either push or pull
other charged material.
1. Start by asking the students the following questions:
a. Have you ever received a “shock” from another person or some object?
b. Have you ever deliberately “shocked” someone?
c. How did you “charge” yourself so that you could shock someone? If
students have any experience doing this it would most likely involve shuffling
their feet along carpet. Tell the students that when they do this they are building
up extra charge on themselves and when they touch someone some of that charge
jumps to the other person. The main thing the students should get is that
building up a charge in that situation requires rubbing or friction.
2. Tell the students that they will learn other techniques to charge objects other than
themselves. Tell the students that the Van de Graph generator produces a charge
on the metal ball. Tell the students that they are going to discover some other
things that charge can do other than just shock people, similarly to what they
experienced with the Van de Graph generator.
3. Have the students cycle through the following stations experimenting with the
effects of charged objects. Have the following directions posted at each station.
Station 1
Directions: Rub the felt up and down on the plastic charging rod. Turn on the
faucet so that a small steady
stream of water comes out of it.
Now bring the charged rod
near the stream of water and
observe what happens. Is the
water charged or not? How do
you know?
Station 2
Directions: Using a string,
hang a pen from a ruler
between two desks (see the
diagram to the right). Now
charge the PVC charging rod
and bring it close to the pen.
What happens? Now charge
the hanging pen by holding
on to the pen cap and rubbing the pen on the piece of felt for twenty to thirty
seconds. Once again charge the PVC charging rod and bring it near the pen.
Now what happens?
Station 3
Directions: Take a twelve inch square piece of plastic wrap and spread it out flat
on the desk. Now place your index fingers underneath the sides of the plastic
wrap, half way up from the bottom
(see the diagram). Slowly pick up
the plastic wrap and observe what
happens. Now lay the plastic wrap
back down on the desk and use the
felt to rub the top of the plastic
wrap, rubbing it for at least twenty
seconds. Now pick up the plastic
wrap, like before, and observe what happens. Can you explain what is causing
this to happen?
Station 4
Directions: You will need two inflated balloons. They should
each have a line to divide the balloon in half with an X
marked on one half. Rub the X side of each balloon on your
hair. Lay the balloons on the table near each other with X sides
facing one another. What happens? Repeat but lay them with
an X and an unmarked side facing one another. Now what
happens? Discuss
Station 5
Directions: Rub the balloon on your head and bring it close to the sugar or
Styrofoam packing peanuts on the surface of the desk. What happens?
Station 6
Directions:
a. Place two strips of tape on the table or desk. Peel them off and bring them
close to one another. What
happens?
b. Now place one strip of tape on
the desk and another strip
directly on top of the first strip.
Pull the strips off of the table
and separate them (This
produces two different types of
charge, one type on each tape
strip). Bring them close to one
another. What happens?
4. Ask the students to share what they learned from the activities at the stations. If
the students have trouble articulating what they learned ask them the following
questions:
a. What are some ways to charge an object?
b. What are some things that charged objects can do?
c. Do charged objects have an effect on other charged objects?
d. Do charged objects have an effect on non-charged objects?
Tell the students to give specific examples from the stations when explaining what they
learned, or when they are answering the questions.
Activity #3
Effects of Static Charge
Description: This student activity allows students to see how the even distribution of
charge on a surface can explain the behavior of the charged objects in the previous
activity and the Van de Graph generator.
4.3.16 Investigate and describe that without touching them, material that has been
electrically charged pulls all other materials and may either push or pull
other charged material.
6.3.23 Explain that electrical circuits provide a means of transferring electrical
energy from sources such as generators to devices in which heat, light,
sound, and chemical changes are produced.
**This activity requires a good amount of space. It would be best to perform this
activity in a large classroom with the desks pushed to the side.
1. Tell the students that they are all going to take part in a simulation that will help
them understand the effect of a build up of charge on objects.
2. Ask the students what they learned about the effect charged objects have on one
another. (Answer: they push each other away or are attracted to one another.)
3. Ask the students: “If objects that have the same kind of charge on them push
each other away what do you think similar charges do to one another.” Answer:
They also push each other away.
4. Setup up the ropes as shown in the diagram below. Attach a twenty foot rope
between two desks. This will act as your surface. Now attach several ten foot
ropes at equal intervals long the length of the first rope.
5. Tell the students that the rope attached between the desks represents the surface
of a rigid object (something that cannot bend) and the other ropes which are
attached to the first rope represent other objects that are connected to the first
and are free to move around. The students may not realize it yet, but this is
meant to represent several situations which they have already experienced: the
paper strips on the Van de Graph generator and the hair on their heads.
6. Tell the students that you are going to find out what happens when they act like
charges that move around on the surface of objects that repel one another / push
one another away. Tell them the only two rules to follow are:
a. They have to be holding on to some part of the rope because the charges,
once on the surface of an object move around on its surface.
b. They have to get as far away from everyone as they can. They must go to
a place on the rope as far away from every other student as possible.
In the end, the students should be spaced similarly to the diagram below:
7. Once the students have stopped moving and have reached some sort of
equilibrium ask them the following series of questions:
a. What do you notice about how you are spaced along the ropes? The
students should be evenly spaced along the ropes, no student should be closer to
another than the rest. You may have to help direct a little traffic throughout the
activity.
b. How did your presence affect the position of the ropes? Are the ropes
positioned differently then how they were originally positioned? The ropes
are now extending straight out from the rope tied between the desks.
c. Is this idea of things sticking straight out or straight up similar to any
charged object that you have seen in the last couple of days? This is similar
to the paper strips on the Van de Graph generator, before the sphere had charge on
it the paper strips were laying down against the sphere, but after the generator
was turned on and the sphere was charged the paper strips stood straight up. It is
also like the individual pieces of hair that stood up on one of the student’s heads
when he/she was charged.
8. The next part of the activity involves students applying their newly found
knowledge of the interactions between charges to predict the motion of electrons
in a simple circuit (a single wire connecting the two terminals of a battery) Show
the students the first diagram of the simple circuit on the overhead projector.
Both diagrams are found at the end of the unit plan.
9. Explain that you can think about a battery with one side having a lot of electrons
and the other side with very little to no electrons in it. The negative side has the
excess of charge / electrons and the positive side has a shortage of charge /
electrons.
10. Now show only the top half of diagram #2 and ask the students the following
series of questions:
a. What do you think will happen if you connect a single wire to the
negative and positive side of the battery? Electrons can move through a
wire. The electrons will move from the negative side to the positive side of the
battery.
b. When do you think the battery will be “dead” or “used up”. When will
that happen? When there are an equal number of electrons on the positive side of
the battery as the negative side then the electrons will cease to flow and the
battery will be “dead”. There will then be an even distribution of charge and the
electrons will not move. This is shown on the bottom half of diagram #2.
11. Explain that anything that allows electrons to flow through it is called a
conductor and any material that does not allow electrons to flow through it is
called an insulator. Circuits use conductors to move electrons from one side of
the battery to the other, usually some type of metal such as copper. Explain that
a simple circuit can be defined as anything that provides a path for electrons to
flow from one side of a battery to the other. A “closed circuit” is a complete
path from one side of the battery to the other; if there is a break in the pathway
so that the electrons cannot flow from one side of the battery to the other then
the circuit is called an “open circuit”. Also explain that all electronic circuits use
moving electrons to do many different types of things.
12. Explain that moving electrons can do many different types of things: produce
light, heat, sound, and motion.
13. Ask the students to think of examples of electronic circuits that produce light,
heat, sound, or motion. …
Simple Circuit Diagram #1
Simple Circuit Diagram #2
Activity #4
Playing with Circuits
Description: Students gain experience with simple circuits. The students will be asked
to perform a series of tasks and record how they performed those tasks on the student
worksheet. They will investigate how to construct series and parallel circuits and also
compare the two general types of circuits.
4.2.3 Make simple and safe electrical connections with various plugs, sockets,
and terminals.
8.3.19 Investigate and compare series and parallel circuits
This activity requires series and parallel circuit kits. They can be purchased from
Castlewood Scientific (http://castlewood1.com/20013.html) or made from parts from your
local Radio Shack and home improvement store. This activity could also be done with
three light bulb holders, eight alligator clips and a battery holder, it’s just messier!
1. Review the concepts discussed during the prior lesson: simple circuits, closed
circuits, open circuits, etc… Tell the students that they are going to investigate
different ways to make circuits.
2. Divide the students up into groups, distributing the circuit boards and the
corresponding student worksheet.
3. The worksheet directs the students to perform certain tasks by connecting the
light bulbs and the batteries in different ways with the provided wires. Tell the
students that when they complete a task, they must record how the wires are
connected to the different terminals by drawing the wires on the diagram on the
worksheet. These worksheets will provide some accountability and allow you to
formally asses the students’ success with the activity. Each student group must
complete the following tasks:
a. Make one light bulb light up.
b. Arrange the wires so that two light bulbs light up. Make it so that if either
one of the light bulbs is unscrewed and taken out, the other light bulb will
stay on.
c. Arrange the wires so that all three light bulbs light up. Make it so that if
any of the light bulbs are unscrewed and taken out, the remaining light
bulbs will stay on.
d. Arrange the wires so that all three light bulbs light up. Make it so that if
any of the light bulbs are unscrewed and taken out, the remaining light
bulbs will turn off.
4. Use the overhead of the circuit diagram to review students’ answers to the
activity. As you discuss each task, have students come up to draw how they
connected their wires with a dry-erase marker directly on the overhead. For each
example discuss the direction and path the electrons take as they travel from the negative
side (black wire) to the positive side (red wire) of the batteries. Trace the path / paths on
the overhead for the students to see.
a. Introduce the term “series circuit”: This refers to a simple circuit where
the light bulbs are connected in such a way so the electrons have only one
choice of path to follow to get from the negative side of the battery to the
positive side. If there are three light bulbs in the series circuit, then the
electrons have to travel through all three light bulbs during their journey
from one side of the battery to the other. (Refer to problems two and three
from the worksheet for examples of series circuits) Discuss how taking one
light bulb out, breaks the path, and the electrons can no longer move from
one side of the batter to the other. Also because the electrons are no
longer moving, the other light bulbs will no longer light up.
b. Introduce the term “parallel circuit”: This refers to a simple circuit where
there are multiple paths for the electrons to take to get from the negative
side to the positive side of the battery (problem number four from the
worksheet is an example of a parallel circuit). Using the diagram on the
overhead show the students how even if one light bulb is taken out and
that path is broken, there are two other paths for the electrons to take from
the negative to the positive side. Hence, the remaining light bulbs will
continue to stay lit, because the electrons are still moving through them.
Student Circuit Worksheet
Names: ____________________________________________
Directions: Try to perform each task below included in the worksheet. Once you have
completed each task, record how the wires are connected on the circuit board. For each
problem, show how the light bulbs and the batteries are connected by drawing in the
wires on the diagrams.
1. Make one light bulb light up. Record
where you placed the wires on the diagram
below.
2. Arrange the wires so that two light
bulbs light up. Make it so that if either
one of the light bulbs is unscrewed
and taken out, the other light bulb will
stay on. Record where you placed the
wires on the diagram below.
3. Arrange the wires so that all three light
bulbs light up. Make it so that if any
of the light bulbs are unscrewed and
taken out, the remaining light bulbs
will stay on. Record where you placed the
wires on the diagram below.
.
4. Arrange the wires so that all three light
bulbs light up. Make it so that if any
of the light bulbs are unscrewed and
taken out, the remaining light bulbs
will turn off. Record where you placed
the wires on the diagram below.
Series and Parallel Circuit Overhead