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Homework Help: Lightning problem?

  1. Jan 30, 2005 #1
    HI, i have this problem that i've been working on, i get 5 tries to get it right, and i only have one try left, so i have to get this right.

    O-16-3 Supposed that during a thunderstorm, the corona discharge from a dissipative lightning rod into the surround air amounts to 0.799 x 10-4 C of positive charge per second.
    (a) If this discharge goes on more or less steadily for an hour, how much electric charge flows out of the lightning rod?
    (b) How many electrons flow into the lightning rod from the surrounding air?

    i submit my wrong answers, and it give a hint, which is:
    The total charge is the charge per second times the number of seconds. The charge on an electron is 1.6 x 10-19 C. Divide the total charge, by the charge on an electron to find the number of electrons.

    which is what i thought i've been doing. but i guess not. I multiply the .799x10-4 by 60. But its always wrong. I've had to do it with different numbers every time, and its always off by a factor of about .016. If i divide my answer by .016, i get something close to the right answer, but not close enough. I don't understand why its that far off everytime, or what i'm supposed to be doing. PLEASE HELP!!!

  2. jcsd
  3. Jan 30, 2005 #2


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    How many seconds in an hour ?
  4. Jan 30, 2005 #3
    Oh my god.... I am sooo dumb. Heh.. ya thats probably it. Heh... i feel stupid... :redface: Thanks a bunch, i probably never would have realized that.

  5. Jan 30, 2005 #4


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    No prob. :smile:
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