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## Homework Statement

The switch is initially open, closes at t = 0, and then reopens at t = 0.5. Find iL(t).

## Homework Equations

## The Attempt at a Solution

i really have no idea how to do this. i have a series RLC circuit at t=0-, t=0.5 and the circuit with the 18V source at t=0, t=0.5-.

I got iL(0)=iL(0-)=

__0__

Vc(0)=Vc(0-)=

__0__

iL(0.5)=iL(0.5-)=18V/6ohm=

__3A__

Vc(0.5)=Vc(0.5-)=5ohm*3A=

__15V__

iL'(0.5)=vL(0.5)/L=15/2 =

__7.5 A/s__

a = R/2L (series)= 7ohm/4 =

__1.75__

w0 = LC^(-1/2)=1/sqrt(2/17)=

__2.92__

__underdamped__because a<w0.

so far is this right? and also i have no idea how to find a single equation iL(t) for t=0-, t=1.5-, and also t=infinity. what do i do??