- 1). Verify that the power supply is turned off.
- 2). Connect the positive terminal of the 12-volt power supply to the first terminal on light bulb No. 1. Connect the second terminal of light bulb No. 1 to the first terminal of light bulb No. 2. Connect the second terminal light bulb No. 2 to the negative terminal of the power supply.
- 3). Turn on the power supply and set the voltage to 12 volts. Because this circuit has two light bulbs connected in series, the voltage drop across each light bulb is 6 volts.
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