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Twinflower
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Homework Statement
C = 1 uF
E = 12 V
Total R in circuit = 100 Ω
Q = 0 before the breaker closes
Problem A:
Derive an expression for the voltage across the capacitor and the current through the circuit as a function of time after the breaker closes.
Homework Equations
This is my first problem. I do not know any relavent equations.
The Attempt at a Solution
I have trouble starting this exercise, but from what I have found on Wikipedia, the capacitor needs 5τ to fully charge, and 1 τ = R times C.
From what I understand, the voltage across the capacitor will decrease until the capacitor is fully charged.
But that comes in conflict with my understanding about that a capacitor will have a voltage across when fully charged (maybe only when there is no other voltage sources present?)
Please kick me in the right direction here, so that I can get going :)