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In a LCR circuit capacitance is changed from C to 2 C. For the resonant frequency to remain unchanged, the inductance should be changed from L to
- L/2
- 2L
- 4L
- L/4
Correct answer: L/2
Solution
In an LCR circuit, the resonant frequency is determined by the formula f = 1/(2π√(LC)). When the capacitance is doubled from C to 2C, to keep the resonant frequency constant, the inductance must be halved from L to L/2, as this compensates for the increased capacitance.
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