(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Consider an RC circuit in which a capacitor is being charged by a battery connected in a circuit. Initially the capacitor is uncharged. Then the switch is closed.

After a time equal to 4.5 time constants, what percent of the final charge is present on the capacitor?

2. Relevant equations

Q = Q_{o}[1 - e^ (-t/RC)]

3. The attempt at a solution

I picked a value of 100 for Q_{o}

so

Q= 100 [1 - e^ (-t/4.5)]

my approach was going to be to find Q and then see wht percent that is of the initial charge Q_{o}

but I dont know wht to put in for the time "t"

please help me out

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# Homework Help: RC circuit final charge

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