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प्रश्न
To reduce the resonant frequency in an LCR series circuit with a generator ______.
विकल्प
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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उत्तर
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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