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Homework Help: Resistors in series and in parallel

  1. Mar 6, 2013 #1

    !20V battery.I need to Find Voltage, Resistance and Current in all resistors and total.
    This is what I did so far.
    Added 13ohms +15 ohms, then took all 3 of those and made it into one, whihc gave me 7.2258ohms.
    Did the same for the 72 and 45 to get 27.7 ohms.
    Then found the total resistance as 77.92 ohms. Found I total , current to be 1.54A
    And for the 19ohm resistors I got V=29.26V I=1.54A
    For 24ohm, V=36.96 I=1.54A
    And I think for the 32 ohm V=29.26 I=0.91A
    For 72ohm and 45 ohm V=27.7ohm and if that is it, should total current equal 1.54 instead of 0.88A?
  2. jcsd
  3. Mar 6, 2013 #2


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    Homework Helper

    How did you get the voltages in red?

    The voltage is the same across all parallel connected resistors. It is equal to their resultant multiplied by the total current. The voltage across the 32 Ω resistor is the same as the voltage across the parallel resultant: 7.226*1.54. Dividing this voltage by the individual parallel resistances, you get the currents.

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