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Ac circuit

  1. Apr 15, 2006 #1
    im stuck on this question and was wondering if anyone could help point me in the right direction:
    a half wave rectified voltage is described by: v(t)=100.sinX
    (that X is mean to be theta)
    when applied to a 50 ohm resistor find the average and rms values of the current.

    thanks an help is much appreciated....
    a stuggling student:grumpy:
  2. jcsd
  3. Apr 15, 2006 #2


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    Gold Member

    The key word there is average. The average value of any curve equals the area of that curve divided by its length. In order words, take the integral of the sine wave from 0 to pi then divide by the length of the curve which is pi in this case. Once you find the average voltage it is possible to find the average current using ohms law.
    Last edited: Apr 15, 2006
  4. Apr 16, 2006 #3
    okay i will certainly give that a good try thanks
  5. Apr 17, 2006 #4


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    Staff: Mentor

    No, after an ideal half-wave rectification, you will have v(t) = 100 |sin(x)|. Be sure to average the absolute value version of the excitation. Hint -- You can calculate the average for a half-cycle of the sine first....
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