If the voltage across a fixed capacitor is doubled, the amount of energy it stores (a) doubles; (b) is halved; (c) is quadrupled; (d) is unaffected; (e) none of these. Explain.

Short Answer

Expert verified

The correct answer is option (c) is quadrupled

Step by step solution

01

Understanding the capacitance of a capacitor

The capacitance of a capacitor does get affected by the change in the voltage across the capacitor and energy stored in it. It depends on the separation between the plates and area of each plate.

02

Evaluation of the change in amount of energy

The relation of energy stored in a capacitor is given by,

\(E = \frac{1}{2}C{V^2}\)

Here, Eis the energy stored, Cis the capacitance and Vis the voltage.

In the above relation, the energy stored in the capacitor relies on the voltage supplied, which means that it increases with a rise in voltage. Here, if the voltage is doubled, the energy will become quadruple because of the square of the voltage.

Thus, option (c) is the correct answer.

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FIGURE 16-32

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