Alternating Cur...

The self inductance of a choke coil is 10 mH. When it is connected with a 10 V dc source, then the loss of power is 20 watt. When it is connected with 10 volt ac source loss of power is 10 watt. The frequency of ac source will be

In an LCR circuit R = 100 ohm. when capacitance C is removed, the current lags behind the voltage by π/3. When inductance L is removed, the current leads the voltage by π/3. The impedance of the circuit is

A group of electric lamps having a total power rating of 1000 watt is supplied by an ac voltage E = 200 sin(310t + 60° ). Then the r.m.s. value o the circuit current is

Following figure shows an ac generator connected to a \"block box\" through a pair of terminals. The box contains possible R, L, C or their combination, whose elements and arrangements are not known to us. Measurements outside the box reveals that
e = 75 sin (sin ωt) volts,
i = 1.5 sin (ωt + 45° )
amp. The wrong statement is

A resistor R, an inductor L and a capacitor C are connected in series to an oscillator of frequency n. If the resonant frequency is n_r, then the current lags behind voltage, when

The instantaneous values of current and voltage in an ac circuit are i = 100 sin 314 t amp and e = 200 sin (314 t + π/3) V respectively. If the resistance is 1 Ω, then the reactance of the circuit will be

What will be the self inductance of a coil, to be connected in a series with a resistance of π√3 Ω, such that the phase difference between the e.m.f. and the current at 50 Hz frequency is 30°

The phase difference between the voltage and the current in an ac circuit is π/4. If the frequency is 50 Hz then this phase difference will be equivalent to a time of