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Homework Help: How much work to move a charge?

  1. Jul 24, 2006 #1
    I was wondering if anyone could tell me the formula for work?

    I have to answer this question:

    How much work does a 12-V battery do in pushing 2mC of charge through a circuit containing 1 light bulb.
    A. .006 J
    B. .012 J
    C. .024 J
    D. The answer depends on the type of bulb in the circuit.

    Well either there is a formula I dont know, or the choice d is right. I was thinking about d, that it depends on the bulb. Because if the bulb would some how provide resistance or stop the circuit that could prevent the charge from moving....So thats a possibility, and then if theres some formula I dont know, then I need that to solve for an answer.

  2. jcsd
  3. Jul 24, 2006 #2
    well work is the potential energy difference - and in this case its qV
  4. Jul 25, 2006 #3


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    A definition of potential difference (or voltage) is work done per unit charge; [itex]V = \frac{W}{q}[/itex]. Re-arranging this gives [itex]W = qV[/itex], as fargoth said. This definition of potential difference is useful to remember.
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