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Question
To reduce the resonant frequency in an LCR series circuit with a generator ______.
Options
the generator frequency should be reduced.
another capacitor should be added in parallel to the first.
the iron core of the inductor should be removed.
dielectric in the capacitor should be removed.
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Solution
To reduce the resonant frequency in an LCR series circuit with a generator another capacitor should be added in parallel to the first.
Explanation:
At response XL = XC ⇒ ω0L = `1/(ω_0C)`
⇒ ω0 = `1/sqrt(LC) "rad"/sec`
⇒ v0 = `1/(2pisqrt(LC)) Hz`
Resonant frequency in an L-C-R circuit is given by
`v_0 = 1/(2pisqrt(LC))`
If L or C increases, the resonant frequency will reduce.
To increase capacitance, we must connect another capacitor parallel to the first.
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