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**[SOLVED] Overdamped RLC circuit**

## Homework Statement

In a parallel RLC circuit determine [tex]i_R(t)[/tex].

R = 20 mohms

L = 2mH

C = 50 mF

v(0+) = 0 (capacitor)

i(0-) = 2mA (inductor)

My question is what is [tex]i_R(0^+)[/tex]? According to my final answer, it should be 0. However, went I graph it with PSPICE, it looks like it starts out somewhere at -186mA. I know that i_R can change instantaneously but the graph that pspice makes, makes it look like it will never be 0. I was under the impression that if the voltage of the capacitor is 0 then iR(t) will be 0 regardless of the current in the inductor. Is this correct?

## Homework Equations

[tex]\alpha = 500 Hz[/tex]

[tex]\omega_0 = 100 Hz[/tex]

[tex]i_R(t) = Ae^{-10.10t} + Be^{-989.9t}[/tex]

## The Attempt at a Solution

Using these two equations

A + B = 0

[tex]i_c(0+) + i_L(0+) + i_R(0+) = 0[/tex]

[tex]RC di_R/dt = -2 mA[/tex]

[tex]i_R(t) = -2e^{-10.10t} + 2e^{-989.9t} mA[/tex]

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