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Homework Help: DC volts and amps

  1. Dec 11, 2009 #1
    1. The problem statement, all variables and given/known data

    The fastest, most powerful Class III battery charger available is supposed to recharge 8.8 kWh into a Chevy Volt battery pack in 15 minutes. What is the most likely combination of DC volts and amps to do this and why?

    2. Relevant equations

    W=VxI (I = amps)
    a 120 V unit can do 12 I in 6 hours

    3. The attempt at a solution
     
  2. jcsd
  3. Dec 11, 2009 #2
    If I remember correctly, P = IV (not the work, but the rate of work -- power). That would mean that you would have 8.8 [kWh]/15 [min] = I*V (be sure to convert the units appropriately). For DC circuits, I would assume the most likely condition would be the one with an appropriately large V/I ratio (more voltage and less current would imply less power loss from resistance).
     
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