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Figure shows an RC potentiometer to measure ac voltage. It is desired that V0/Vi should be independent of frequency. The value of C should be

10 μF
11 μF
0.1 μF
0.09 μF

Correct Answer: 10 μF

Explanation:

Since resistances are in the ratio of 10 : 1, capacitances should be in the ratio of 1 : 10 because X_C ∝ 1/C.

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