1. We will be in Read Only mode (no new threads, replies, registration) for several hours as we migrate the forums to upgraded software.

Superposition Problem

Discussion in 'Homework Help' started by markmc001, Oct 2, 2008.

  1. markmc001

    Thread Starter Member

    Mar 10, 2008
    Hi all,
    I a have just started a new course and am already feeling like I'm out of my depth with the level of work in some classes! I am struggling with a superposition theorem problem. Could anyone help the the following problem?

    Calculate the value of the current in branch PQ using Superposition

    I have attached a schematic of the circuit.

    Thanks in advance,
  2. The Electrician

    AAC Fanatic!

    Oct 9, 2007
    Read the sticky at the top of the first page of the forum.

    You should show the work you've done so far in your attempt to solve the problem.
  3. markmc001

    Thread Starter Member

    Mar 10, 2008
    I don't necessarily want the answer but would appreciate it if someone could walk me through the steps of how to approach the question.
  4. hobbyist

    AAC Fanatic!

    Aug 10, 2008
    If I remember correctly, superposition means to calculate what each individual source contributes to the entire circuit. By disabling every source but one, then calculate the effect it has on the circuit, then continue disabling sources and enabling each source one at a time calculating each individual contribution to the circuit. Than algebraicly add the total effect (calculated) of the sources together.

    But first you need to convert your component values to reactances. C=Xc L=XL
    then take it from there.
  5. ee_govcont

    New Member

    Oct 3, 2008
    Disabling the sources means to short the unused voltage supplies and open unused current supplies.

    The reactances for L and C are jwL and 1/jwC.

  6. scubasteve_911

    AAC Fanatic!

    Dec 27, 2007
    As your instructor what the initial conditions are, otherwise you can only get a steady-state solution. If you are truely to find current as a function of t, then you need the initial conditions.

    Can you use laplace circuit analysis?