Introduction to Electric Circuits
Introduction to Electric Circuits1
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Electricity is an important and necessary component
to our daily lives. Electricity delivers energy to
many of our appliances/electronics and an electric
circuit describes the pathway it takes.
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In this first activity, students will focus on
what is needed/ required for electrical
devices to work. For example, what do we
need to make a light bulb light up?
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Physical Sciences Connection: Conservation of Energy and Energy Transfer (PS3.B)
Initial thoughts:
Imagine you have a small light bulb. What do you think is
required to make the light bulb light up?
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For the arrangements below, predict whether the light bulb will light up.
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Prediction:
Observation:
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Prediction:
Observation:
Prediction:
Observation:
Some of the material here is taken from Physics and Everyday thinking by Fred Goldberg.
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Introduction to Electric Circuits
What information did you use to make your predictions? What made you decide whether
the light bulb would light or not light up?
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Discuss your thoughts and ideas as a class.
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Activity 1: What is needed to light the light bulb?
In this activity you will construct an electric circuit to determine in what instances the
light bulb will light up.
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What you will need:
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One battery
One light bulb
Two wires
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Part 1: Comparing different electric circuit arrangements
Using the materials given to you, recreate each of the arrangements an figure out If the
bulbs lights up, write “yes” next to “observation” and “no” if it does not light up.
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Part 2: A new circuit arrangement
Think of another arrangement where the light bulb will light up.
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Draw the arrangement below in the box below.
What does your electric circuit
have in common to the electric
circuits drawn above?
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Introduction to Electric Circuits
Look over the arrangements that allow the bulb to light and answer the following
questions.
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Which parts of the battery need to be part of the electric circuit?
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Does a wire or part of the bulb need to touch the positive end of the battery only? Or can
it touch any part of the positive end of the battery?
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Which parts of the bulb must be part of the electric circuit?
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Part 3: New tools for constructing an electric circuit
It can be awkward to hold the battery, wires, and bulb to build an electric circuit. To make
things easier, there are special holders to help us
construct these circuits!
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Construct the circuit to the right. Does the
lightbulb light up?
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The lightbulb should light up like before, but
hopefully it was easier to do this time.
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Introduction to Electric Circuits
Activity 1 Recap:
For a lightbulb to light up we have discovered the following:
• A battery is needed
• Wires are needed to connect the light bulb to the batter
• The positive and negative sides of a battery are both used
• The bottom and side of the light bulb are used
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Activity 2: Understanding what parts of the battery need to be connected in an
electric circuit.
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What you will need:
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Two batteries
One light bulb
Two wires
The evidence form the past few sections suggest that one side the light bulb needs to be
connected to the positive end of the battery and the other side of the bulb needs to be
connected to the negative end of the battery.
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But do the two sides of the bulb need to be
connected to the positive and negative ends
of the same battery?
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Do you think the lightbulb will light up? Why?
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Introduction to Electric Circuits
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Part 1: Construct the arrangement above.
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Does the bulb glow?
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Do the two ends of the bulb need to be connected to the two ends of the same battery for the
circuit to work?
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Activity 2 Recap:
• The positive and negative parts of a battery need to come from the same battery
otherwise the lightbulb will not light
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Activity 3: Understanding the different parts of a light bulb
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Construct an electric circuit as shown here:
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Which part of the light bulb is actually glowing?
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Introduction to Electric Circuits
Below is a sketch showing the various parts of a bulb:
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Starting at one end of the battery, draw connecting lines that go from the two wires to the
filament support, then to the filament.
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The connections from the battery form a continuous pathway to the filament (the part
that lights up) then back to the battery. We’ll look into this more in the next activity.
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Activity 3 Recap:
• Only one part of the light bulb lights. This part is called the filament.
• The connections from the battery form a loop.
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Introduction to Electric Circuits
Summarizing Questions
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The picture below shows one electronic circuit that was
constructed by a student.
Do you think the light bulb will light?
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Using what you have discovered about electric circuits,
explain why the light bulb will or will not light.
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