1. Sep 5, 2013

DODGEVIPER13

1. The problem statement, all variables and given/known data
Determine the load impedance for the circuit depicted in fIG 11.40 if the source is operating at a PF of (a) 0.95 leading: (b) unity: (c) 0.45 lagging.

2. Relevant equations

3. The attempt at a solution
uploaded. I am not really sure what to do please see attachment.

2. Sep 5, 2013

Staff: Mentor

Attachment not showing for me...

3. Sep 5, 2013

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4. Sep 5, 2013

Staff: Mentor

So what are the relevant equations? How does power factor affect the measured impedances? TBH, it's pretty hard to read your upload. It would be much better if you could learn to type your equations into your question threads

5. Sep 6, 2013

DODGEVIPER13

well PF=P/((Ieff)(Veff)), Ieff=Im/sqrt(2), Veff=Vm/sqrt(2), apparent power= (Veff)(Ieff), P=IV. PF depending on whether it is leading or lagging it can be purely resistive or reactive.

6. Sep 6, 2013

DODGEVIPER13

So A impedance value would have a reactive and resistive component. In (a) it is leading so purely resistive correct so it would just be the resistor value for R and I have a current so I can find V.

7. Sep 6, 2013

milesyoung

What does the power factor of the load tell you about the angle between the voltage across it and the current through it?

Anyway, you need more information than you have provided in the problem statement to determine both the angle and magnitude of the 'load' impedance. Are you sure you've included everything you were given?

8. Sep 6, 2013

DODGEVIPER13

yah that's it. I uploaded the circuit diagram if that helps R= 1000 ohm and I= 275(20 degrees) mA. Load, resistor, and current source are all in parallel

9. Sep 6, 2013

DODGEVIPER13

lets see here the current leads voltage here so capacitive load.If I am right then the cosine^-1(.95)=18.19 degrees?