Help with EE homework...

JohnCU

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Dec 9, 2000
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The question states: The frequency of the source voltage in the circuit is adjusted until i is in phase with v. What is the value of w in radians per second?

The circuit is a voltage source, then a 500 ohm resistor and 1 uF cap in series, followed by a .5H inductor and 1000 ohm resistor in parallel. The equivalent impedance is 500.0025 + j(5w-1000000)... what do I do to solve for w? I don't know anything about i or v except that they are in phase.

Pic of circuit: here
 

JohnCU

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Dec 9, 2000
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wait, wouldn't it be the frequency that made the circuit purely resistive, cancelling out the j term? So solve 5w - 1000000 = 0?
 

slpaulson

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Jun 5, 2000
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Originally posted by: JohnCU
wait, wouldn't it be the frequency that made the circuit purely resistive, cancelling out the j term? So solve 5w - 1000000 = 0?

Sounds right to me.
 

Stojakapimp

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Jun 28, 2002
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i'm just throwing a bone out there, but would it have anything to do with calculating the phase of the system? I mean, you know the transfer function, right? Then can you just calculate the phase which is tan-1(imaginary/real)? Not sure if that would get you anywhere, but I have no clue what you are learning in your classes right now
 

RaynorWolfcastle

Diamond Member
Feb 8, 2001
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Easy problem, find the frequency at which the impedance is purely real :)

edit: I guess it was covered above, yes that is the right way to do it.