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ok erm, i know how to get the equation V = EMF (1 - e^(-t/RC)) in a RC circuit

but what if i had to take into account the internal resistance r of the voltmeter measuring the voltage across the capacitor? meaning now, the circuit contains a resistor R in series with, an internal resistance r parallel with capacitor C.

so how does the equation becomes V = EMF ( r / R+r) ( 1 - e^-((R+r)t/RrC))

so by kirchoffs law, EMF = voltage across resistance R + voltage across the [parallel capacitor C and internal resistance r]

EMF = RI + q/C , heres the problem, the current through the parallel component will split up into r and C. so how do i form the new equation?

also will the voltage drop across the capacitor still be the same as when there is no r? so, will it still be q/C? or something else?

please help thanks!

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# Homework Help: RC circuits equation

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