How Much Charge Remains on a Capacitor After 4 Milliseconds in a Circuit?

Wizardofwaz
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Homework Statement


A capacitor is charged to 1 coulomb; the capacitance is 6.00×10-5 farads. Then a switch is closed which puts the capacitor in a closed circuit with a resistor; the resistance is 9.20×10^1 ohms. Calculate the charge on the capacitor after 4.00 milliseconds. (1 ms = 0.001 s)



Homework Equations


I=V/R
C=Q/V


The Attempt at a Solution


Final charge=1 Coulomb * 1.602E-19-.004/(92*6E-5)

1.602E(2.71828)^.004/(92*6E-5
 
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You are simply using Q = Qo*e^(-t/tau). And tau = R*C, t = 4E-3 s. Take another look at RC circuits and the charging and discharging capacitor relations.
 
what is e
 
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