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Homework Help: What is the Current?

  1. Feb 16, 2009 #1
    1. The problem statement, all variables and given/known data
    If the resistance of the device were reduced by 15.8 percent, what current would be drawn at 120 V?

    there was a first part of this question which i have already gotten. the question was
    An electrical device draws 2.56 A at 120 V. If the voltage drops by 15.8 percent, what will be the current, assuming nothing else changes? so the resistance is 46.875


    2. Relevant equations
    ok so i believe that i would just do 120/(.158x46.875)


    3. The attempt at a solution
    when i did this i got like 16 A and it was said to be wrong. i am confused on what i did wrong.
     
  2. jcsd
  3. Feb 16, 2009 #2

    Delphi51

    User Avatar
    Homework Helper

    Reducing by 15% means you keep 85% of the resistance. Multiply by .842, not .158.
     
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