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Electrical Power

  1. Mar 3, 2012 #1
    Hey guys why is power conducted at very high voltages? doesnt that increase the current and thus the heat generated because p=v.i?
  2. jcsd
  3. Mar 4, 2012 #2
    You are looking at it the wrong way round, if you are designing an alternator for a given power the current flow will decrease as the voltage increases, having lower current means that you need less copper to conduct the current thus keeping your costs, weight and size down. There is a problem the higher the voltage the harder it is to insulate the windings, as in all engineering you end up with a compromise
  4. Mar 4, 2012 #3

    jim hardy

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    If you're going to dabble in electricity it's important to get straight in your head the basic quantities' names and meaniings


    The answer to your question is in your question: ""because p=v.i? ""
    Indeed , Power = volts X amps
    To transmit a given power, the more volts you have the fewer amps you need to accomplish that.

    old jim
  5. Mar 16, 2012 #4
    Just to throw my two cents here;

    Technically P = V*I*cos(θ)
    So, in order to have a small amout of current, which also reduces losses in power lines (P = R * I^2), you need a higher voltage.
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