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Homework Help: Circuts and Light Bulbs

  1. Apr 21, 2008 #1
    1. The problem statement, all variables and given/known data
    Two Light bulbs, one rated 30W at 120V and another rated 40W at 120V are arranged in two different circuits.
    a) they bulbs are connected in parallel to a 120V source

    determine the resistance and current in both bulbs.

    b) determine the resistance and current if they are connected in series

    2. Relevant equations


    3. The attempt at a solution

    I took the power over the voltage to find the current and then plugged that in to V=IR, but how does the voltage and current differ when it splits, or when it is in series?
  2. jcsd
  3. Apr 21, 2008 #2
    The load voltages for a parallel configuration is the same across each load. Each light in the parallel configuration has the same voltage.

    For a series configuration the load voltages add to equal the source voltage.
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