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How a Motor or Generator works?

  1. Apr 20, 2003 #1
    How a Motor or Generetor works ???
  2. jcsd
  3. Apr 20, 2003 #2
    Re: M/g

    I'm assuming you mean an electric generator as opposed to a generator ran by fuel?

    In this case I searched google and found this site:
    How a generator works.

    Also, if this is not what you wanted a google search (with quotes " ") will do wonders for you, the sites usually provide for pictures, which don't seem to work well on PF.
  4. Apr 20, 2003 #3


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    Staff: Mentor

    Re: M/g

    Since harnessing and creating electricity work the same way, apply electricity to a motor and it spins. Spin a motor and it becomes a generator.

    Its just rotating electromagnets.
  5. Apr 22, 2003 #4
    But what is the basic difference between AC and DC machines???

    What is eddy current loss???

    why tranformer rating is not KW why it is KVA???
  6. Apr 23, 2003 #5


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    Staff: Mentor

    ac is alternating current, dc is direct current (constant). KVA is used because KW doesn't take into account phase for ac.

    Not sure about eddy currents.

    Maybe you should use google. It sounds like you have a lot of basic questions and you can find some quick answers there.
  7. Apr 23, 2003 #6


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    Gold Member

    Yea...DC has a constant voltage(like when u connect a circuit to a battery...its always going to be , say, 12 Volts...(well not really since the battery has internal resistance, and i think the voltage goes down as the battery gets older...maybe not...))..
    But in AC the voltage varies sinusoidaly...For example, most american outlets are 120 V and 60 hz..this means that the voltage goes between 120 and -120 60 times in a second...(correct me if im wrong, please..i might be mistaken on some details_)
  8. Apr 23, 2003 #7


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    Science Advisor

    Hertz is a unit of frequency - a full
    cycle is when you return to your original
    position - back AND forth.
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