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Math-U-Up

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## Homework Statement

See attached image for circuit diagram and givens.

The switch has been closed for a very long time.

a) What is the charge on the capacitor?

b) The switch is opened at t=0 s. What current initially flows?

## Homework Equations

V = IR

Q=CV

I=I

_{0}e

^{-t/(RC)}

## The Attempt at a Solution

Since the switch has been open for a long time, no current flows through the 10 Ohm resistor. Therefore,

I = 100V/(60 Ohm + 40 Ohm) = 1 Amp, V = 1Amp*40 Ohm, and Q = 2uF * 40V = 80uC.

So my question is: Is the current that initially flows after the switch opens at t=0 s just due to the battery? So it would just be 1Amp? I'm having trouble understanding how to find the current at part b.