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Homework Help: Extra Que for Interest: Voltage and Wire Resistance

  1. Feb 23, 2009 #1
    Hi! I was looking at notes about voltage and resistance, and this question popped into my head.

    1. The problem statement, all variables and given/known data
    If a certain length of wire ie)40m with an unknown resistance has a voltage of say 24V (random number) when hooked up to a battery, how does the voltage change throughout the circuit, or does it? ie) when a voltmeter is hooked up to a 10m segment of the wire anywhere on the wire, would the voltage increase or decrease?


    2. Relevant equations
    P=IV
    R=pL/A


    3. The attempt at a solution
    I'm not sure, but if i were to guess I would think of the wire as any other resistor and assuming resistance is constant throughout predict the same voltage? I'm probably completely off, but it's worth a shot.

    Thanks!
     
  2. jcsd
  3. Feb 23, 2009 #2

    LowlyPion

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    Homework Helper

    By your second equation you have said you've traveled a 10m distance ... so what would the R be at that point?

    Since it is something anyway, and if you are traveling from the positive terminal of the battery, then if there is a ΔR, there must be a ΔV.

    Increase from the positive terminal? Does that really make sense? Of course the ΔV is going to be a drop.
     
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