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AC generator problem

  1. Jun 25, 2006 #1
    Hello guys

    I am having a problem understanding the wording of a question, perhaps someone can help me explain it.

    The alternating voltage of a generator is represented by the equation

    E = Eo sin wt,

    where E is in volts, Eo = 346V, w = 685 rad/s, and t is in seconds.

    Find the voltage output of the source. Answer in units of V.

    I've found that w = 2pif where f is the frequency of the generator, which gives me 109.021 Hz in the frequency, that was part 1 of the problem. However I can not find any formula that relate to this voltage output. I thought at first it was asking for E and to use Eo and sin 685 to get the answer but that was not the right one. What do you guys think the question is asking for?
  2. jcsd
  3. Jun 25, 2006 #2


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    (1)The question wishes you to calculate the voltage at a defined time and the time was omitted by mistake.

    (2)The question requires to to calculate the rms voltage, in which case almost all of the information is superfluous.

    Is this the whole question or is there subsequent questions using the same function?
  4. Jun 25, 2006 #3
    the question didn't give me a t to work with so I don't think it's asking for the voltage at a instant time.

    but it did turn out it was just asking for rms voltage..... wish the question was worded more clearly :yuck:

    thanx Hootenanny for your tip :smile:
  5. Jun 25, 2006 #4


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    My pleasure :smile:
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