Open and Short Circuits
Does the "short circuit" mean the electricity takes a shorter course?
What do you need?
- Lantern battery - DO NOT USE ANYTHING HIGHER THAN A NINE-VOLT BATTERY
- Small light bulb/lamp or small motor
- Wire to connect battery and lamp terminal (bare wire, not plastics or rubber covered)
- Wire clippers
What to do?
- Cut three pieces of wire.
- Connect the wires from the battery terminals to the lamp terminals - lamp or motor will light up or run.
- Take third piece of bare wire and drop across the two bare wires leading between the terminals - notice what happens. The lamp or motor should go out or stop.
- Take the third wire that was laying across the other two wires. Take the wire clippers and cut one of the wires leading from the battery to one of the lamp terminals. The lamp or motor should also go out or stop.
What you'll discover!
When the third piece of wire was dropped across the two wires leading to and from the lamp, the wire created a "short circuit." This doesn't mean the electricity took a shorter course, it just took an easier path.
When you cut the wire with the clippers, you created an "open" circuit. If you placed a switch on this wire... you would create the same type of circuit you have with any electric light.
Reprinted with the permission of the California Energy Commission. © 1994-2008 California Energy Commission.
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