I have an RL parallel circuit. The AC voltage is 120 and the frequency is 60 Hz. One branch has a resistor (60 ohms) and the other branch(the one parallel to the resistor) has an inductor with 60 mH.
The inductive reactance of my inductor is
My question is this, to find the impedance I use Z = 1/(sqrt([1/60]^2 + 1/[22.61]^2)) ?
-- conrad
If that's what the textbook says, then, obviously, yes.
Good Luck! Rich
I don't do it that way. First I decide what's reasonable, and since you have a 60 ohm resistor across the source, the total impedance must be less than 60 ohms. The currents are 90 degrees out of phase, so the solution is to vector the resistor current at 90 degrees from the inductor current, get the result, and then convert that to impedance at some angle.
The resistor current will be 120/60 = 2 amps, and the inductor current will be 120/(6.28*60*.06) = 5.31 amps. The total current will be sqrt(5.31^2 + 2^2) = 5.67 amps. Therefore, the impedance will be
120/5.67 = 21.15 ohms. And you can figure out the phase angle.-Bill
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