Engineering AC Circuit using circuit parameters - HELP

AI Thread Summary
The discussion revolves around solving an AC circuit problem involving voltage, current, and power calculations. The user is uncertain about their calculations for voltage Vab, which is derived from the difference between voltages Va and Vb, and seeks clarification on the total current calculation. They express confusion regarding the total current, believing they have already computed it. Additionally, the user calculates the active power dissipated in resistors and the reactive power in the inductor but is unsure about the correctness of their answers. The request for a schematic indicates a need for visual aid in understanding the circuit parameters better.
Sirsh
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Hey guys, Just need some help with this question, It asks for the answers to be in circuit parameters:
http://tinypic.com/r/k0k2ed/5
For some reason I don't think my answers are correct as I'm finding it hard to make sense of my answers to the questions.
a)Find the voltage Vab (magnitude and angle)
Vab = Va-Vb
current going to the first two resistors: I1=(V\angle0)/(2R)
current going through resistor and inductor: I2 = (V\angle0)/(R+Xl\angle90)
Itotal = I1+I2 = (V\angle0(3R+Xl\angle90))/(3R+2RXl\angle90)

Va=It*2R = (V\angle0(3R+Xl\angle90))/(3R+2RXl\angle90)*2R = (V\angle0(3R+Xl\angle90))/(R+2RXl\angle90)

Vb = It*(R+Xl\angle90) = (V\angle0(3R+Xl\angle90))/(3R+RXl\angle90)

Vab = Va-Vb
Therefore: (V\angle0(3R+Xl\angle90))/(R+2RXl\angle90) - (V\angle0(3R+Xl\angle90))/(3R+RXl\angle90).

Not sure if that's right.. A little insight would be appreciated!

b) Calculate the active power dissipated in each reistance.

Power dissipated in resitor/s (R) = I^2*R = ((V\angle0(3R+Xl\angle90))/(3R+2RXl\angle90))^2*R

Power dissipated in inductor = 0.

c) Calculate the reactive power dissipated in Xl.

Q = I^2*jXl = I^2*Xl\angle90 = ((V\angle0(3R+Xl\angle90))/(3R+2RXl\angle90))^2*Xl\angle90

d) calculate the total current
Now this is where I am confused it asks me to calculate the total current now even though i thought I already have.. Is this wrong?

Thanks a lot guys.
 
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Is there a schematic to accompany this?
 

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