The electromotive force is , where
is capacitance in farads,
is resistance in ohms,
is charge in coulombs.
Substitute in
.
Substitute and
.
Apply integral on each side.
\
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The initial condition is when
.
Substitute and
in
.
.
Substitute in
.
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The limiting value of charge is .
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The limiting value of the charge is .
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The limiting value of the charge is .