Author Topic: Help with complex wave equation  (Read 1991 times)

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Offline KSPTopic starter

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Help with complex wave equation
« on: May 21, 2014, 01:26:08 pm »
Hi all

I need a hand with the attached problem. Yes, it is an assignment, so I know the whole moral issue of someone giving me the answer, but if you could just point me in the right direction I would be very grateful.

I can probably do everything else once a) is done, but I can't remember how to work out the current from the complex voltage

Cheers

 

Offline TMM

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Re: Help with complex wave equation
« Reply #1 on: May 21, 2014, 01:38:25 pm »
divide the complex voltage by the complex impedance of the resistor and inductor in series ... don't forget that the impedance is different for each frequency ;)
 

Offline T3sl4co1l

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Re: Help with complex wave equation
« Reply #2 on: May 21, 2014, 11:27:55 pm »
I* = V* / R

(using * to indicate a phasor quantity)
(Ed: well, to be fair... R --> Z* is a phasor too, and works just the same.  Oh, I forget if there's a conjugate in there too.)

Do this at each frequency (mumble mumble superposition something).

Or if you're a masochist,

V = (bunch of sin terms as a function of t)
= I*R + L * dI/dt

Solve for I.

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 

Offline KJDS

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Re: Help with complex wave equation
« Reply #3 on: May 22, 2014, 08:29:35 am »
I perked up seeing the title, fully expecting to see something relating to Schrodingers wave equations, but instead get something less complex and the route to solving it already explained.

Offline T3sl4co1l

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Re: Help with complex wave equation
« Reply #4 on: May 23, 2014, 02:51:03 am »
You can still show us the solution for the hydrogen atom if you want to  :-[    :P

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 


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