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The formula for a capacitor discharging is $Q=Q_0e^{-\frac{t}{RC}}$ Where $Q_0$ is the maximum charge. But what property defines the maximum charge a capacitor can store?

If it depends on capacitance then that means it depends on the voltage you put across the capacitor, but how can any capacitor "cope" with any voltage?

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The maximum charge a capacitor stores depends on the voltage $V_0$ you've used to charge it according to the formula:

$$ Q_0=CV_0 $$

However, a real capacitor will only work for voltages up to the breakdown voltage of the dielectric medium in the capacitor. So in reality, for every capacitor there is a maximum possible charge $Q_{max}$ given by:

$$ Q_{max}=CV_{max} $$

where $V_{max}$ is the breakdown voltage of the dielectric medium in the capacitor.

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  • $\begingroup$ I don't think this answers the whole question. $C$ may be the constant for a given capacitor but there are factors like the surface area of the plates in the capacitor that affect $C$. $\endgroup$ – Brandon Enright Apr 4 '13 at 23:23
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    $\begingroup$ @BrandonEnright Yes, but I think the question is what the maximum charge is for a given capacitor. There is no maximum charge for an arbitrary capacitor. $\endgroup$ – jkej Apr 5 '13 at 0:07

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