Calculating Charge on a Capacitor in a Circuit with a Switch

AI Thread Summary
The discussion focuses on calculating the charge on a capacitor in a circuit after the switch is closed. The relevant formula for charge is q = Q(1-e^(-τ/(R⋅C))), where τ is the time constant. The user attempted the calculation but arrived at 0.00632 mC, which is incorrect. Clarification is sought on the correct approach, particularly regarding the value of Q, which is not 10^-5 C. Accurate application of the formulas and understanding of the time constant are crucial for determining the charge correctly.
Gillian
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For the circuit shown in the figure, the switch S is suddenly closed with the capacitor uncharged. After one time constant, the charge on the capacitor is closest to:
19-20x.jpg

a) 2.0 mC
b) 0.74 mC
c) 1.0 mC
d) 1.3 mC
e) 0.00 mCRelevant Formulas
q = Q⋅(1-e-τ/R⋅C)
τ = RC

My Attempt
q = Q(1-e-τ/T)
q = (10⋅10-6)(1-e-1)
q = (10⋅10-6)(1-.36788)
q = (10⋅10-6)(0.632)
q = 6.32⋅10-6 C = 0.00632 mC

I am not sure how else I would approach this problem. Any suggestions?
 
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Q is not ##10^{-5}## C.
 

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