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Back EMF equation, need help

  1. Nov 6, 2016 #1
    1. The problem statement, all variables and given/known data
    An A/C starter has a 12V supply & a back EMF of 6V. If the resistance is 0.1 ohms, calculate current during start-up & while in operation

    2. Relevant equations
    Not sure what else? Sorry im stuck.

    3. The attempt at a solution
    Start up current
    12V=I x .01
    I = 120A

    operating current
    6V=I x .01
    I = 60A
  2. jcsd
  3. Nov 7, 2016 #2


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    Homework Helper
    Gold Member

    Looks correct.
  4. Nov 7, 2016 #3


    User Avatar

    Staff: Mentor

    What is A/C an abbreviation for?
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