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Homework Help: Whats the average current does this rotating charge represent

  1. Feb 25, 2009 #1
    1. The problem statement, all variables and given/known data

    a small sphere carries a charge of 8.34nC in whirled in a circle at the end of an insulating string. The angular speed is 116 Pi rad/s. whats the average current does this rotating charge represent

    2. Relevant equations

    I= q/t
    w= theta/t

    3. The attempt at a solution
    116 pi rad/sec * 1 rev/min
     
  2. jcsd
  3. Feb 25, 2009 #2

    LowlyPion

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    Re: Ch17-18

    What is current?

    What units are you asked to represent it in?

    It might be useful to figure how many times the charge will pass a particular point a sec.

    They give you that it revolves at 116π radians/sec so how many times a sec ?
     
  4. Feb 25, 2009 #3
    Re: Ch17-18

    Current is I (amps) where its charge(Q) / (t) times in secs. so 116/60?, is it 8.34x1e-9/ (116 pi/60)?
     
  5. Feb 25, 2009 #4

    LowlyPion

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    Re: Ch17-18

    1. How many radians in a revolution?

    2. What's with the 60, when they give you ω in radians/sec already?
     
  6. Feb 25, 2009 #5
    Re: Ch17-18

    116 pi rad/ sec * 60secs/1 min* 1rev/2pi rad
     
  7. Feb 25, 2009 #6

    LowlyPion

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    Re: Ch17-18

    Why do you want it in radians/minute when current is in amps which are Coulombs/s?
     
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