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Homework Help: Calculate the current being drawn from a battery

  1. Jan 1, 2004 #1


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    If I have a question asking to calculate the current being drawn from a battery can I, or rather should I, give an answer in Ohms?

    I hate electricity...

    Thanks and a Happy New Year to you all.

  2. jcsd
  3. Jan 1, 2004 #2
    Resistance is measured in ohms. Current is measured in amps.
  4. Jan 1, 2004 #3


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    Hi Jim

    Thanks, the penny is dropping...

    I have been given the voltage and the resistances

    So I guess I can work out the total resistance and then use P = V^2/R

    and from there P = V/I > I = V/P

    Just thinking aloud but I would be grateful if you could confirm that I am on the right track.


  5. Jan 1, 2004 #4
    Wouldn't it be easier to use Ohm's Law?

  6. Jan 1, 2004 #5


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    Thanks Doug

    "What's that?", you probably heard me say...

    Yes, I got it, thanks very much.

  7. Jan 2, 2004 #6

    Actually, E is more commonly used to symbolize voltage. The unit of measure for voltage(E) is the Volt(V). E = 10V for example. Anyway,

    [tex] P = E I [/tex]

    So to calculate the current with a given Voltage and Power:

    [tex] I = \frac{P}{E} [/tex]

    You could save yourself a step and use

    [tex] I = \frac{E}{R} [/tex]
    Last edited: Jan 2, 2004
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