Electronics and Communication Engineering - Measurements and Instrumentation - Discussion

Discussion Forum : Measurements and Instrumentation - Section 1 (Q.No. 19)
19.
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
Answer: Option
Explanation:

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

Discussion:
2 comments Page 1 of 1.

Gunjan said:   5 years ago
For making any circuit independent of frequency time constant of first ckt should be equal to second ckt. In the case of 10 k and 1 microfard capacitor time constant will be r*C=10k*1micro farad. Now in below part time constant is 1k*c. Put both times equally and find c that will be equal to 10microfrad.
(1)

Shruthishravya said:   8 years ago
Please explain.

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