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Homework Help: Simple Resistance Problem help

  1. Jan 31, 2008 #1
    Simple Resistance Problem...help!!!

    1. The problem statement, all variables and given/known data
    A wire has a resistance of 0.008 W. What will the wire's resistance be if it is stretched to seven times its original length without changing the volume of the wire? (Give answer in W.)

    2. Relevant equations

    R = Ch in V / I

    3. The attempt at a solution
    I thought I would just multiply 0.008 by 7? But thats not right...I know this must be so easy but for some reason I am stuck!!
  2. jcsd
  3. Jan 31, 2008 #2
    does anyone know how to do this?
  4. Jan 31, 2008 #3
    how resistance can be measured in watts instead omms? Maybe power which going through wire is 0.008 W and if wire will be 7 times longer then power will be 7 times smaller or resistance will be 7 times bigger. But possible that resistance will be 7*7=49 times bigger becouse, if you would have 7 times longer wire it would have 7 times bigger resistance, but becouse wire is also 7 thiner, then at all resistance will be 49 times bigger.
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