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Homework Help: Circuit puzzler

  1. Sep 22, 2004 #1
    Please help me wif these problems!!! I have no idea.
    A person with a body resistance between his hands of 10 kohms accidently grasps the terminals of a 20 kV power supply.
    (a) Draw a circuit diagram including all the data.
    (b) If the internal resistance of the power supply is 2000 ohmns, what is the current through his body?
    (c) What is the power dissapated in his body?
    (d) If the power supply is to be made safe by increasing its internal resistance, what should the internal resistance be for the maximum current in this situation to be 1.00 mA or less?

    Thanks 4 ur help!!!
  2. jcsd
  3. Sep 22, 2004 #2
    Hi Alonzo

    All your questions can be answered if you do part (a) correctly. You haven't included your solution here. First, please do so, so that we know where you're going wrong/facing difficulty.

    First off, I'd say you have a power supply (a power source--a seat of emf in this case), a <few> resistance(s) in the circuit.

    1. What is the expression for current in a circuit containing a seat of emf V and resistance R?
    2. What is the expression for the power?
    (Hint: Think about Ohm's Law)
    3. What is your specific problem with this?

    Last edited: Sep 22, 2004
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