20 Physics -- Capacitor

A capacitor has a vacuum in the space between the conductor plates. If you double the charge on each conductor, what happens to the capacitance?

1 Answers

When charge is given to a capacitor the potential difference across its plates rises. As the more and more charge is given, its potential increases accordingly. If a charge Q is given to the capacitor so that its potential rises through V, then it has been found that charge Q stored in it is directly proportional to potential difference V across the plates of the capacitor. So,

Q ∝ V

Q = CV

where C is a proportionality constant, called the capacitance of the capacitor. Its value depends upon the shape and size of two conducting surfaces, their separation and the nature of the dielectric medium between them. Thus, we have

C=Q/V

Hence, there is no effect on the capacitance of the capacitor if we double the charge on each conductor.

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Polar Dielectric:

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