# Help me solve the RLC differential Equation~!

#### kiki998

Joined Mar 18, 2009
3
Pls help me solve it the circuit is there....

#### mik3

Joined Feb 4, 2008
4,843
Assign currents in the circuit and then use KCL to relate the voltages. You have to end up with a second order differential equation.

#### kiki998

Joined Mar 18, 2009
3
means how i not so clear about it #### kiki998

Joined Mar 18, 2009
3
can help me find out the differential equation?

#### mik3

Joined Feb 4, 2008
4,843
can help me find out the differential equation?
Just use a method of circuit analysis but instead of using the frequency domain (impedances) to analyze the circuit represent the voltage or the current for an inductor or capacitor with their derivative function.

v=Ldi/dt

i=CdV/dt

#### hitmen

Joined Sep 21, 2008
161
After looking at your problem I realise that I dunno how to do it too

Vi + V(R1) + 1/C∫ i dt = 0

(1/C)∫ i dt + L (di/dt) + v(R2) = 0

Vi + V(R2) + L di/dt + V(R2) = 0

I remember it being somewhere in last sem notes but I cant seem to recall how to do it

#### GirishC

Joined Jan 23, 2009
58
After looking at your problem I realise that I dunno how to do it too

Vi + V(R1) + 1/C∫ i dt = 0

(1/C)∫ i dt + L (di/dt) + v(R2) = 0

Vi + V(R2) + L di/dt + V(R2) = 0

I remember it being somewhere in last sem notes but I cant seem to recall how to do it
Now apply Lapalce transform..do arithmatic...solve by PD and take inverse Laplace...vola...you get the answer