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Quick question about power lines and E=IxR

  1. May 17, 2012 #1
    Ok so I have read that power lines carry very high voltage to minimize loss through resistance, but when I take a look at the formula

    E=IxR
    E=Voltage
    I=Current
    R=Resistance

    Divide both sides to get

    E/I=R

    To minimize R we should make the numerator of the quotient smaller, and the denominator larger (I.E. 1/1,000,000) To get a small value for R right?

    This would in turn, mean cranking up the current, and lowering the voltage :confused:

    I know I am wrong, as the companies get good results from cranking up the voltage. I can't find my error though.

    Thanks Guys :D

    -Dave
     
  2. jcsd
  3. May 17, 2012 #2
    The power loss is actually I2R, so minimizing current minimizes losses.
     
  4. May 18, 2012 #3
    R is fixed, a material property of the aluminum/iron that the wires are made of. You are minimizing power loss as Bob S said.
     
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