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Homework Help: Current/Frequency Question

  1. Apr 18, 2010 #1
    1. The problem statement, all variables and given/known data
    A beam of electrons is hitting a block of metal with current A. What is the frequency they are hitting the block?


    2. Relevant equations
    i=q/t


    3. The attempt at a solution

    i=q/t => 1/t=i/q. So then 1/t=A/e, where e is the elementary charge.
    This may in fact be right. Our prof gave it to us as a question to think about and I want to know what everyone else is thinking.
     
  2. jcsd
  3. Apr 19, 2010 #2

    Andrew Mason

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    Let dn/dt = the number of electrons per unit time flowing (ie. the frequency at which electrons hit the block).

    What is the current in terms of dn/dt?

    AM
     
  4. Apr 19, 2010 #3
    Wouldn't that just be like I said, the current divided by the charge, thus saying how many electrons per unit time. [A]/[C] * e=[C*s]/[C]=1/[C] * e = 1/ electrons.
     
  5. Apr 19, 2010 #4

    Andrew Mason

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    It was not clear what you meant by t or 1/t. The number of electrons per second is the Current (in coulombs/sec or Amperes) divided by the charge of one electron (in Coulombs). If that is what you meant by 1/t then you were correct.

    AM
     
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