Engineering RC circuit with dc current source

AI Thread Summary
The discussion revolves around solving for the current in each branch of an RC circuit with a constant current source. The user attempted to apply the mesh method but found it confusing, particularly when substituting the impedance of the capacitor. There is uncertainty about how to approach the problem, especially regarding the second part, which asks for the time-dependent voltage across the current source. Suggestions include using differential equations or Laplace transformations, and the need for an initial condition, such as the capacitor voltage being zero at t=0, is noted. Overall, the user seeks clarity on both the circuit analysis and the interpretation of the problem's requirements.
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Homework Statement


Solve for the current in each branch of the following circuit as a function of time & derive and expression for the time dependence of teh emf of the constant current source in the circuit below.


Homework Equations



Zc = Xc = 1/(wC) = t/(2pi*C)


The Attempt at a Solution



I attempted to use the mesh method:

Loop 1:
-1000(i1)+50-(Zc)(i1)+(Zc)(i2)=0

Loop 2
-(Zc)(i2)+(Zc)(i1)-3500(i2)+3500(i3)=0

Loop3:
-3500(i3)+3500(i2)-5000(i3)-V=0

This quickly got confusing when I substituted Zc for t/(2pi*120mF).
I have no idea how to solve this problem when it has both a capacitor and a current source.

I also do not understand what the second part of the question is asking.

I would appreciate any help/insight that you could offer. Thanks.
 

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We can't see your picture until it's been approved, but I can tell you that for these kind of questions, usually, you have to either use differential equations or Laplace transformations. I assume you're familiar with one of them?

The second part gets me too. I can understand each word separately, but put them together and it's jibberish to me. :blushing:
 
The 2nd part asks for the voltage across the current source, as a function of time.

As a start, you could get the steady-state currents and voltages (t→∞).

To solve this, I think we need some initial condition that isn't given. For example, perhaps the capacitor voltage is zero at t=0?
 
That's all the information that I'm given. I have a feeling that since the current varies with time that I have to treat it like an ac circuit, and put in a function instead of i. I'm meeting with my prof today, so hopefully he provides some more insight.
 

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