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A capacitance of 2 μF is required in an electrical circuit across a potential difference of 1.0 kV. A large number of 1 μF capacitors are available which can stand a potential difference of not more than 300 V. The minimum number of capacitors required to achieve this is:

1. 2
2. 16
3. 24
4. 32

Correct answer: 32

Solution

To achieve a total capacitance of 2 μF at a potential difference of 1.0 kV using 1 μF capacitors rated for 300 V, we must connect the capacitors in series and parallel configurations. Each series connection of three 1 μF capacitors can withstand 900 V, and to reach 1.0 kV, we need at least four such series groups in parallel, resulting in a total of 32 capacitors.

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