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Circuit Problem?

I need to determine the equivalent resistance and the total amount of power that was dissipated by the resistors.

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5 Answers

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  • 12 months ago
    Favorite Answer

    Resistors in series simply add

    Resistors in parallel can be solved with 1/Rt = 1/R1 + 1/R2 + 1/R3....

    or if only two resistors, then Rt = (R1 * R2)/(R1 + R2)

    Once you combine all the resistors into one equivalent resistor across the battery you can use Ohm's law to determine the amount of current in the resistor. 

    Power = Voltage * Current.

  • 12 months ago

    Req=2+2=4//4=2+10=14//12=168/26=6.46+4=  10.46Ω

    P=E^2/R=25/10.46= 

    2.39W

  • 12 months ago

    R6 & R7 are in series:

    =>Resultant(Rr) = R6 + R7 = 2 + 2 = 4Ω

    Now Rr & R5 are in parallel:

    =>1/Rr = 1/4 + 1/4 => Rr = 2Ω

    Now Rr and R4 are in series:

    =>Rr1 = 2 + 10 = 12Ω

    & R2 & R3 are also in series:

    =>Rr2 = 4 + 8 = 12Ω

    Now Rr1 & Rr2 are in parallel:

    =>1/Rr = 1/12 + 1/12 =>Rr = 6Ω

    Now Rr & R1 are in series:

    =>R(net) = 4 + 6 = 10Ω

    Thus by P = V^2/R

    =>P(total) = (5)^2 /10 = 2.5 W

  • 12 months ago

    R6 and R7 and in series and add up to 4

    that is in parallel with R5, and combine to 4/2 = 2

    that is in series with R4, total 12

    R2,3 in series add up to 12

    that in parallel with the other 12 equals 6

    and that in series with 4 equals 10 Ω

    total current = 5/10 = 0.5 amps

    total power = 5 x 0.5 = 2.5 watts

    for R1, voltage drop is 2 volts, so power is 2x0.5 = 1 watt

    0.5 amps into the network to the right of R1, which is 6 Ω, produces a voltage of 3 volts, which gives you a current into R2 and R3 of 3/12 = 1/4 amp

    etc

    etc

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  • 12 months ago

    5,6,7 are in parallel

    1/4 + 1/4 = 2/4 = 1/R so R = 2 ohm

    that parallel combo is in series with 4

    R = 2 + 10 = 12 ohm

    all the above is in parallel with 2 and 3

    1/12 + 1/12 = 2/12 = 1/R so R = 6 ohm

    all the above is in series with 1

    4 + 6 = 10 ohm total R

    then

    P = V I = 5v * 10 ohm = 50 watts

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