How Does Time Affect Current in a Series RC Circuit?

AI Thread Summary
In a series RC circuit with a 120V emf source and a time constant of 4.00 seconds, the initial current is 8.00 mA when the circuit is completed. As time progresses, the current decreases and approaches zero as time reaches infinity. The mathematical relationship governing the charge and current involves the equation q=Q(1-e^(-t/RC)), where Q is the maximum charge. To find the current at infinity, applying limits shows that the current ultimately becomes zero. Understanding the behavior of current in relation to time is crucial in analyzing RC circuits.
Ryll
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A capacitor that is initially uncharged is connected in series with a resistor and an emf source with Є=120v and negligible internal resistance. Just after the circuit is completed, the current through the resistor is 8.00 mA, and the time constant for the circuit is 4.00 s

What is the current as time reaches infinity? prove mathmaticly

My questions is don't know where to start I know it has something to do with q=Q(1-e_-t/RC) but must be missing something
 
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Welcome to the forums Ryll,

I'll give you two hints. Firstly, current is the rate of flow of charge. And secondly, one could make good use of limits in this question :wink:
 

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