KVL KCL application help

Discussion in 'Homework Help' started by n_adam, Mar 16, 2014.

  1. n_adam

    Thread Starter New Member

    Mar 1, 2014
    Hi guys,

    I can't figure out how to solve this problem. To find the power dissipated in each resistor I need to find all the currents or voltages.

    In the 16 ohm resistor using ohms law I calculated the current which is 5 A, so the power dissipated is 400W.

    I tried going on from here by writing KVL equations for the 3 loops, but I end up with 4 unknown currents.

    Can somebody help me with figuring out what am I missing here?
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  2. shteii01

    AAC Fanatic!

    Feb 19, 2010
    I just did Mesh Current Method on your circuit. I got 3 meshes, 3 mesh currents, 3 equations. I just solved the 3 equations.

    The mesh made of 30-5-16 Ohm resistors has 5 Amperes mesh current according to my solution. This is the same mesh current that passes through the 16 Ohm resistor. Like you said, since the voltage across this resistor is given, we find that current through that resistor is 5 Amperes. So my Mesh Current Method solution matches Ohm's Law solution for that resistor.

    Lets see your mesh current equations.
  3. WBahn


    Mar 31, 2012
    By telling you the voltage across the 16Ω resistor they paved the road for you.

    Q1) What is the voltage across the 15Ω resistor?

    Q2) What is the voltage in the 15Ω resistor?

    Q3) Given current in the 16Ω resistor and the 15Ω resistor, what is the current in the 5Ω resistor?

    Just keep walking yourself across the diagram asking what voltage or current can I solve for next.
  4. n_adam

    Thread Starter New Member

    Mar 1, 2014
    Oh thank you guys I got it it was pretty easy, I tried to overcomplicate it...