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Homework Help: Sin curves and currents

  1. Sep 30, 2007 #1
    1. The problem statement, all variables and given/known data
    what is the frequecy F for the alterating current
    U(T)=15cos(314t) A

    2. Relevant equations
    Am really new at this kind of problem but i think 314 is how many times the current rotates or fluxuates in 1 period so the F has to be the distance between waves?

    3. The attempt at a solution


    314/2pi i get 493.23 but i know thats wrong
  2. jcsd
  3. Sep 30, 2007 #2
    Are you sure 314/(2pi) is 493.23? Check with your calculator properly :wink:
    Last edited: Sep 30, 2007
  4. Sep 30, 2007 #3
    [tex]U\propto cos(\omega t) ~~~~ \omega = 2\pi \nu [/tex]

    So you should divide 314 with 2pi, not divide 314 with 2 and then multiply with pi.
  5. Sep 30, 2007 #4
    ok i see what i did worng forgot the darn ( ) on the calc. man these ( ) always screw me.

    thank you both
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