Frequency in a circuit using complex notation

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hockeynut
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Homework Statement



The frequency, ω, of the source in the circuit of Figure 2 is adjusted until ig is in phase with vg.

(a)using complex notation, determine the value of ω (rad/sec)
(b)if vg = 20 sin ω t [where ω is the frequency found in 2(a)], determine an expression for the output voltage, v0



Homework Equations





The Attempt at a Solution


See attached attempt on Question A & B - can someone advise if it looks right?
 
Attachments
  • Handwritten working on lined paper for a phasor circuit problem: a schematic with a source, series 5 ohm resistor and 1 microfarad capacitor, a 1 kilohm resistor and an inductor, followed by impedance equations solved for omega, ending with omega = 20 rad/sec.
    Solution Q2 a.jpg
    18.9 KB · Views: 522
  • Handwritten working for Q2(b) of a circuit problem, solving for the output voltage in the time domain using complex impedances and phasors, ending with v0 = 35.02 sin(20000t + 1.63°) V.
    Solution Q2 b.jpg
    14.6 KB · Views: 527
I think your frequency ended up being one order of magnitude too high. Check your math.
 
Thanks gneill.
Ah so where I have 10 to the power of 8, it should be to the power of 6?
 
hockeynut said:
Thanks gneill.
Ah so where I have 10 to the power of 8, it should be to the power of 6?

Well, you've got both 106 and 108 in the relevant area of your work, so you really should be more specific. But yes, that is the issue.