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Homework Help: Confusion regarding electrical power

  1. Oct 23, 2008 #1
    From P=(V^2)/R, it suggests that as you increase the resistance, you decrease the electrical power.

    Conversely, from P= (I^2)R, it suggests taht if you increase the resistance, you increase the electrical power.

    Please can someone explain the above.

    Thanks alot
  2. jcsd
  3. Oct 23, 2008 #2


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    Homework Helper

    Both of the presumptions are based on holding either V or I constant in determining power.

    The real relationship is P = V * I.

    R is a passive element that relates V and I.
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