Calculating Charge on a Capacitor in a Circuit with a Switch

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SUMMARY

The discussion focuses on calculating the charge on a capacitor in a circuit after the switch is closed. The relevant formula used is q = Q(1-e^(-τ/R⋅C)), where τ is the time constant defined as τ = RC. The user initially calculated the charge as 0.00632 mC, which is incorrect. The correct approach involves using the given values for Q, R, and C to determine the charge after one time constant, leading to the conclusion that the charge is closest to 1.0 mC.

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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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