The power factor in an $L-C-R$ circuit at resonance is

$A$ series combination of a resistor of resistance $100\,\Omega$,an inductor of inductance $1\,H$,and a capacitor of capacitance $6.25\,\mu F$ is connected to an $AC$ source. The quality factor of the circuit will be $.............$.

In a series $LCR$ circuit,a resistor of $300 \ \Omega$,a capacitor of $25 \ \text{nF}$ and an inductor of $100 \ \text{mH}$ are used. For maximum current in the circuit,the angular frequency of the ac source is $. . . . \times 10^4 \ \text{rad s}^{-1}$.

In a series $LCR$ resonant circuit,the capacitance is changed from $C$ to $3C$. To obtain the same resonant frequency,the inductance should be changed from $L$ to

$A$ series $L-C-R$ circuit containing a resistance of $120 \Omega$ has an angular frequency of $4 \times 10^5 \ rad \ s^{-1}$. At resonance,the voltage across the resistance and the inductor are $60 \ V$ and $40 \ V$ respectively. The value of the inductance is: (in $mH$)

What is resonance in an $LCR$ series circuit?