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Homework Help: EMF Problem

  1. Mar 29, 2010 #1
    1. The problem statement, all variables and given/known data
    A current of 22 amperes flows in a heater coil whose resistance is 5 ohms. What E M F in volts is required?

    2. Relevant equations

    3. The attempt at a solution
    Not quite sure where to begin. I'm thinking the internal resistance, R, is inherent w/the circuit so EMF must be greater than the velocity calculated.

    Velocity =IXR=22x5=110
    EMF=V +IR = 110 + 22x5=220 volts
    Any comments here on if this is correct?
  2. jcsd
  3. Mar 29, 2010 #2
    Just V=IR
    Review your variables before you plug and chug. V here is not velocity, it is the EMF.
  4. Mar 29, 2010 #3
    So this would be ohm's law?
    V=IR -->
    EMF=(22)(5)=110 Ohms
  5. Mar 30, 2010 #4
    Yeah, should be. Except the units of EMF is in volts. Resitance is ohms.
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