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## Homework Statement

after having been in position 1 for a long time, the switch was moved to position 2 at t=0. determine:

a) i-c(0-) and vc(0-)

b) i-c(0) and v-c(0)

c) i-c(infinity) and v-c(infinity)

d) v-c(t) for t>=0

e) i-c(t) for t >=0

## Homework Equations

## The Attempt at a Solution

not sure how to find voltages/current of capacitor. i have general equations i think though:

for t=0- (before t=0): v(t)= v(0)e^-t/(RC) = 12e^(-t/4)

i(t)= -Vs/R*(e^-t/(RC))= 300uI*e^-t/4

for t=0 (after t=0): not sure exactly how to find v(t) (which i think in this case is also v(infinity)), but i made an attempt:

find voltage across 60k ohm resistor by doing voltage division, 12(60k/(60k+30k))=8V

v(t)=8e^-t/(RC)

not sure how to find the eq. resistance in this one. should i do 30 || 60?

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