# Differential Ecuation simple circuit

Discussion in 'Homework Help' started by omar-rodriguez, Mar 29, 2016.

1. ### omar-rodriguez Thread Starter Member

Jun 24, 2015
67
2
Hello, I'm trying to find the differential equation of this circuit but I got an Integro differential equation, I don't know what's next because the current function is on terms of tao and t at the same time 2. ### anhnha Well-Known Member

Apr 19, 2012
866
61
You could take derivative with t of both sides and then there is only one variable t.

3. ### omar-rodriguez Thread Starter Member

Jun 24, 2015
67
2
Ok I did it and it looks like that But I have one more quesion, why when I am finding the differential equation, I said that in this case but when I apply laplace for example to a derivative, I have to replace the real values of the initial conditions derivative 4. ### anhnha Well-Known Member

Apr 19, 2012
866
61
The first case Vc(0) is a constant while the second case it is the value of capacitor derivative at the time t equals to 0 (first you derivative Vc and get dVc/dt then you evaluate it at t=0).

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5. ### omar-rodriguez Thread Starter Member

Jun 24, 2015
67
2
mmmmm..... It all makes sense now, thank you so much