Transcript Foundations of Technology Capacitor Teacher Resource Unit

Foundations of Technology
Capacitor
Teacher Resource Unit 4 Lesson 4
© 2013 International Technology and Engineering Educators Association,
STEMCenter for Teaching and Learning™
Foundations of Technology
Objectives:
1.
2.
You will build a simple circuit to show
that a capacitor stores electrical energy.
You will be able to observe the LED get
dimmer as the capacitor discharges.
•Two basic types
•Ceramic disk
•Electrolytic
•Has positive
and negative
sides
•Farads – unit of measure (F)
•Microfarads(uF) and picofarads (pF)
You will need the following parts from your kit:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Breadboard
1000 ohms resistor (brown, black, red, gold)
330 ohms resistor (orange, orange, brown, gold)
1000uF capacitor
100uF capacitor
1 LED (light emitting diode)
9 volt battery lead
2 wires
9 volt battery
Use this schematic to construct the experiment.
330 ohm
1000 ohm
Flow of current
+
+
9 volts
-
Flow of current
Quick Check:
Your circuit should like this one.
1.
2.
3.
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6.
This circuit will make a LED dim.
When electron flow is present, the LED will be
bright.
Capacitors are able to store electrical energy.
The larger the capacitor the more energy it is able
to store.
Electrons flow from the battery through the LED
and resistors.
Electrons will charge the capacitor.
When the battery is removed, the energy stored in
the capacitor will continue to light the LED until it
has been discharged.
1.
2.
3.
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Start with the 1000uF capacitor in place.
Connect the 9 volt battery.
Observe the brightness of the LED.
Disconnect the 9 volt battery.
Observe what happens to the LED.
Replace the 1000uF capacitor with the 100uF
capacitor.
Reconnect and then disconnect the 9 volt battery
Observe what happens to 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. Is the capacitor in the right way?
By completing this experiment, you should have
noticed the light from the LED grew dimmer as the
capacitor discharged when the battery was
removed.
In complete sentences, write what you learned about
a capacitor in a circuit.