Transcript potentiometer lab directions

You will need the following parts from your kit:
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2.
3.
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6.
Breadboard
100 ohm resistor (brown, black, brown, gold)
anode
1 LED (light emitting diode)
cathode
1 Potentiometer
Flat side Shorter lead
9 volt battery lead (connector)
9 volt battery
Use this schematic to construct the experiment.
Flow of current
This wire should hang free
+
9 volts
100 ohms
Flow of current
Notice these
lines are
important
Quick Check:
Copy and label all the components
of the schematic in your notes.
Your circuit should like this one.
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4.
Connect the 9 volt battery.
Observe the brightness of light from the LED.
Turn the shaft on the potentiometer.
Observe the change in brightness of light from the
LED.
Troubleshooting:
1. If the LED does not light up, check to make sure it is in correctly.
2. Check the battery. Does it have voltage?
3. Are there any breaks in the circuit?
4. Are you using the correct wires on the potentiometer?
Answer these questions
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2.
3.
While completing this experiment, what did you
notice about the light from the LED as you
changed the potentiometer?
Which direction do you twist (clockwise or
counter-clockwise) to increase the resistance?
Which to decrease?
In complete sentences, write what you learned
about a potentiometer in a circuit.
This circuit should light the LED. Answer these questions:
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Why is the 100 ohm resistor put in this circuit?
(Think about the experiment with the LED and
resistors)
What is a potentiometer?
The greater the resistance, the ______ the LED
will be. The less the resistance the _____ the LED
will be.
You may find a potentiometer on your CD-player to
adjust the volume from the speakers. Where else
can you find potentiometers? List at least 3.