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Homework Help: A very annoying current electricity problem

  1. Aug 24, 2010 #1
    1. The problem statement, all variables and given/known data
    A battery has an emf=6V. The battery is connected in series with an ammeter and a voltmeter. If a certain resistor is connected in parallel with the voltmeter reading decreases by a factor of 3, and the ammeter reading increases by a factor of 3. What is the INITIAL READING V of the voltmeter? All elements of the circuit have unknown internal resistance. Assume the battery doesn't have any internal resistance

    2. Relevant equations
    R=VI, V=(r/R)*E,

    3. The attempt at a solution
    I keep on going around a circle with this problem. When I start with something I ultimately get nothing but whatever I found earlier. Every time the V(initial) cancels out. May be there is some maths trick. I don't know.
  2. jcsd
  3. Aug 24, 2010 #2


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    Homework Helper

    Draw the circuit diagrams and write out the expressions for the current and voltage readings before and after connecting the resistor. Show your work.

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