Parallel Circuits
Obj:
Analyze parallel circuit with Voltmeter, Ammeter
Materials: V, A meters, bulbs, wires, power source

Methods & Analysis
1.  Sketch 2 bulbs in a parallel circuit with the ammeter and voltmeter properly arranged to read total current and voltage across a single bulb.  Assume that all bulbs are similar.
2.  Wire it (must be checked by certified physics teacher before energizing).  Using the ammeter and voltmeter, record total current and potential difference for each bulb on a VIRP table.  Assume current is equally divided.
3.  Repeat steps 1 and 2 for 3 bulbs in a parallel circuit.
4.  Unscrew one bulb, then 2 bulbs in your 3 bulb circuit.  Record and explain the results.
5.  Write out the rules for parallel circuits.
6.  What happens to the total resistance, amount of current, and power in a parallel circuit as more and more resistors are added?  What happened to the brightness of each bulb during the lab?
7.  Calculate the total charge (q) that would pass in the 3-bulb circuit in 30 minutes.
8.  Calculate the total energy used by the 3-bulb circuit in 60 minutes.
9.  State the differences between the 3-bulb series and 3-bulb parallel circuits with regard to I, V, R, P, and energy.

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