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A capacitor has capacity C and reactance X. If capacitance and frequency become double, then reactance will be

1. 4X
2. X/2
3. X/4
4. 2X

Correct answer: X/4

Solution

The reactance of a capacitor is inversely proportional to both capacitance and frequency, given by X = 1/(2πfC). Doubling both capacitance and frequency results in the reactance becoming one-fourth of its original value, i.e., X/4.

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