Find phase angle of RLC network

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D.B0004
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Homework Statement


Please see attachment for circuit and parameters.

Homework Equations


i --> 90 phase angle for inductor so Z of inductor = 0.5<90
sum of voltages = 0
#<40 = #*cos(40) + i*sin(40)*#

The Attempt at a Solution


shteii01 - 100 + 0.5<90 + V2<theta = 0 --> 100 + 0.5*cos(90) + i*sin(90)0.5+V2*cos(theta)+i*sin(theta)*V2 = 0 --> two unknowns
OR
delta V = I * Z and then take V1 - delta V to find V2. The work seems simple but I get the wrong answer! Note that the answer I have in the attachment was my first solution which I did in my head - not the one I got from the methods shown above. Thanks for the help.
 
Attachments
  • Circuit diagram: a voltage source V1 = V1 angle 0° on the left, a series inductor jXL with current I labelled, and a voltage source V2 = V2 angle delta on the right, with P1, Q1 and P2, Q2 power labels marked at the two ends.
    Screen Shot 2015-02-12 at 6.49.54 PM.png
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I don't understand your first approach because you would appear to be adding voltages and impedances together in some way. But your second approach should work just fine. Since you are given the current you can find the potential drop across the inductor as you say. Can you show the details of that attempt?