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Working of Van De Graff generator

  1. Jul 2, 2010 #1
    In a Van de graff generator, the positive conductor which is connected to the power supply (of high voltage) generates an electric field of high value, which results in dielectric breakdown of air and the positive charge gets "transferred" to the insulated belt. The book says " positive charge is replenished on the conductor by the power supply". My question is, if the path is discontinuous, how can battery replenish the charge? Some positive charge from the negative conductor should flow back to the battery to happen.
  2. jcsd
  3. Jul 3, 2010 #2
    You have to think about the full path of the flow of electricity.

    It flows from the power supply to the discharge electrode, up the belt to the top-load (sphere). Then it either leaks or is discharged as a spark into the surrounding air and back to ground.

    The other side of the power supply is connected to ground, which completes the circuit.

    In electrical circuit theory, the top-load would be seen as one plate of a capacitor, the other being the ground. In this case the capacitor periodically flashes over.
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