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Question
A capacitor has capacitance C. Is this information sufficient to know what maximum charge the capacitor can contain? If yes, what is this charges? If no, what other information is needed?
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Solution
No. This information is not sufficient. Since the charge is proportional to the potential difference across the capacitor, we need to know the potential difference applied across the capacitor.
q ∝ V ⇒ q = CV
Here, q is the charge, V is the potential difference applied and C is the proportionality constant, i.e. capacitance.
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