A variable capacitor is connected to an inductor of inductance 20 mH. For what capacitance will the circuit resonate at a frequency of 1 kHz?

In an L – C – R circuit, capacitance is changed from C to 2C. For the resonant frequency to remain unchanged, the inductance should be changed from L to

The resonance frequency of the tank circuit of an oscillator when $L = \frac{{10}}{{{\pi ^2}}}mH$ and $C = 0.04\mu {\rm{ }}F$ are connected in parallel is

An alternating current source of frequency 100 Hz is joined to a combination of a resistance, a capacitance and a coil in series. The potential difference across the coil, the resistance and the capacitor is 46, 8 and 40 volt respectively. The electromotive force of alternating current source in volt is

The power factor of good choke coil is

The carrier frequency generated by a circuit containing 1 nF capacitor and 10 μH inductor is

When a coil carrying a steady current is short circuited, the current in it, decreases η time in time ${t_0}$. The time constant of the circuit is

An electric bulb and a capacitor are connected in series with an AC source. On increasing the frequency of the source, the brightness of the bulb:

At resonance in an LC circuit, which of the following is true?

The power dissipated in an AC circuit is zero if the circuit is

An LC circuit has a natural frequency of 50 kHz. If the capacitance is doubled and the inductance is halved, the new resonant frequency will be: