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Homework Help: Charging and discharging capacitor

  1. Jan 23, 2012 #1
    I need some help on the interpretation of our laboratory experiment in physics.
    In our lab experiment we charged and uncharged a capacitor. And here are the things we observe.

    1. when one bulb was connected in a circuit across a 4.5 V potential source, the bulb turned on with a bright continuous light.

    2. charging: when the bulb was connected to the three capacitors in a parallel and a compass along the circuit, the bulb blinks once with a weak/low light and the needle of the compass moves clockwise.

    3. discharging: when the potential source was disconnected and the circuit was closed, the bulb blinks once with a strong/bright light and the needle of the compass moves counter-clockwise.

    4. charging: when the ammeter was connected across the capacitors in the circuit composed of light bulb and compass, the needle of the ammeter goes to its maximum and returns gradually with a slow motion down to zero, and there are no reactions with the bulb and the compass.

    5. discharging: when the potential source was disconnected and the circuit was closed, the ammeter goes to its maximum and returns gradually with a faster motion down to zero, and there are no reactions with the bulb and the compass.

    6. charging: when the voltmeter was connected across the capacitors in the circuit composed of light bulb and compass, the voltmeter reading was 8.8V, the bulb blinks once with a low/weak light and the needle of the compass turns clockwise.

    7. after disconnecting the potential source, the voltmeter reading remains.

    8. discharging: when the potential source was disconnected from the circuit and the circuit was closed, the needle of the voltmeter turns back fast to zero, the bulb blinks once with a strong/bright light and the needle of the compass turns counter-clockwise.

    please explain why these observations happen ...
     
  2. jcsd
  3. Jan 23, 2012 #2
    First give your interpretations of each.
     
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