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Homework Help: An ideal (lossless) transformer has 4 times as many turns

  1. Apr 28, 2012 #1
    1. The problem statement, all variables and given/known data
    An ideal (lossless) transformer has 4 times as many turns on the primary winding as it has on the secondary winding. The secordary winding is loaded with a 10k ohm resistor and a sinusoidal voltage source having negligible resistance and a peak voltage of 10V is connected to the primary .

    1. the value nearest to the resistance presented to the voltage source??
    2. the value nearest to the peak current flowing in the secordary winding??

    2. Relevant equations

    Input resistance rin = e1/i1 = e2N1/N2 x n1/i2N2 = e2/i2{N1/N2}^2

    rin = (N1/N2)^2 x RL

    3. The attempt at a solution

    I cant find out the solution 1. & 2., please advise!!
  2. jcsd
  3. Apr 29, 2012 #2


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    Staff: Mentor

    Re: Transformers

    Hi bckcookie! If the primary voltage is 10Vpk, what is the secondary voltage?

    Determine the secondary current with that load of 10kΩ on the secondary.

    Determine the primary current.

    What is the result of dividing primary voltage by primary current?
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