Discharging a Capacitor: How Long Does it Take?

AI Thread Summary
The discussion revolves around determining the time it takes for a 5.0 microfarad capacitor to discharge through a 2000 ohm resistor. The time constant indicates that the charge decreases by a factor of 1/e every 0.01 seconds. A key question raised is the definition of "unmeasurable" charge, which complicates the ability to answer the original question. Without a clear threshold for what constitutes unmeasurable charge, the participant struggles to provide a definitive answer. The conversation highlights the importance of understanding both the mathematical concepts and the practical implications of capacitor discharge.
Jimmy25
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Homework Statement



What is the shortest time after which there would be no measurable charge on a 5.0 microfarad capacitor that is charged, then discharged across a 2000 ohm resistance.

a. 0.001 s
b. 0.5 s
c. 10 s
d. 3600 s

Homework Equations


The Attempt at a Solution



According to the time constant the charge on the capacitor should decrease by a factor of 1/e every 0.01 s according to my calculation.

I don't know how to answer the question though.
 
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How much charge is considered unmeasurable?
 
Last edited:
That's my question. How do I answer this without knowing that?
 

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