Support Material
Possible Circuit investigations
The following investigation ideas would, through practical investigation and careful
questioning help learners to:
Understand what happens in a series circuit with two bulbs when one bulb is removed.
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Learners, in groups, build a series circuit with two bulbs, two 1.5 V cells and crocodile-clip
wires. Learners disconnect / unscrew one of the bulbs and discuss observations. (circuits must
be complete for bulb to light)
Learners draw conclusions can demonstrate understanding in a range of ways, e.g. a talk to
the rest of the class, making a poster with annotated photographs, writing a simple report
Learners could explore the effects of too much current flowing through a bulb e.g. by wiring a
4.5V battery into a circuit and a 1.5V bulb
Learners could research how a bulb works, the role of the filament and why the circuit will not
work if the bulb is blown.
Understand what happens when the number of bulbs or other components in a series circuit
is increased.
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Learners, in groups, plan how to carry out an investigation to test what happens when the
number of bulbs in a series circuit is increased.
Learners predict what will happen as bulbs are added to the series circuit.
Learners add bulbs to the series circuit and note the brightness of all the bulbs, which will be
decreased. (Data-loggers can be used to monitor brightness of bulbs.)
Learners could add other components in series and observe what happens, for example, add
a bulb to a circuit with a motor and a propeller attached, adding a buzzer to a series circuit to a
circuit wired with a motor in it
Understand what happens when the number of batteries in a series circuit is increased.
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Learners, in groups, plan how to carry out an investigation to test what happens when the
number of batteries in a series circuit is increased.
Learners predict what will happen as batteries are added to the series circuit.
Learners add batteries to the series circuit and note what happens to the bulbs. If more
batteries are added to a circuit (remember + to –) then a bulb becomes brighter. Pupils, in
groups, carry out task ensuring it is a fair test. Learners provide explanations, draw conclusions
and make an organised report of their investigation using appropriate illustrations.
Understand how the thickness /length /metallic composition of wires going to a lamp affects
the brightness of the bulb.
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Using concept cartoon 10.4 as a starting point, Learners identify questions to investigate.
Learners, in groups, plan how to carry out an investigation on the above. Learners predict what
will happen if wires going to the bulb are thicker, longer and/or made of different metals. An
ammeter can be inserted into the circuit to ensure more accurate measurement.
Learners, in groups, carry out task ensuring it is a fair test. Learners use a spreadsheet or
graph paper to construct a bar chart of their findings. Learners provide explanations, draw
conclusions and make an organised report of their investigation using appropriate illustrations.
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Support Material
Understand how a simple motor works.
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Learners make observations about the effects of swapping over the connections when wiring
a motor up in a circuit
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Learners research how a simple motor works
Understand and be able to give examples of energy transfers involved in simple circuits
which contain components.
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Learners should be encouraged to consider how energy can be transferred around circuits
and do useful work as in light and heat being given off by a bulb. They could then describe other
examples of energy transfers in circuits with different components e.g. motors, buzzers
Learners could choose a way to demonstrate their understanding of energy transfers e.g.
researching how a particular component works e.g. a bulb in a torch and choosing a way to
communicate this to others e.g. through an annotated diagram, an animated power point slide,
acting out what is going on.
www.educationscotland.gov.uk/STEMCentral