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Homework Help: Really weird one

  1. Feb 11, 2008 #1
    [SOLVED] really weird one

    1. The problem statement, all variables and given/known data A small sphere that carries a charge q is whirled in a circle at the end of an insulating string. the angular frequencyy of rotation is omega [w]. What average current does this rotating charge represent?



    2. Relevant equations I = dQ/dt; w = 2(pi)/T; x[t] = Acos[wt +C];



    3. The attempt at a solution; this question doesnt make sense to me. q never changes - it just travels in a circle - so dq/dt =0;there is one charge going in a circle, but not axially which would represent charge in a conduit. is this a picture of alternating current? [we haven't gotten to that yet].
     
  2. jcsd
  3. Feb 12, 2008 #2

    Shooting Star

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    Current is the net charge per unit time passing a given point. On any point on the circumference, what is that value?
     
  4. Feb 13, 2008 #3
    That would be qw = charge per second. surely not that simple. thanks
     
  5. Feb 14, 2008 #4

    Shooting Star

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    Should be q/T = qw/2pi.
     
  6. Feb 24, 2008 #5
    thanks shooting star!
     
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