Alternating Current

In an ac circuit, an inductor, a capacitor and a resistor are connected in series with $X_L=R=$ $\mathrm{X}_{\mathrm{C}}$. Impedance of this circuit is :

An alternating voltage $V(t)=220 \sin 100 \pi t$ volt is applied to a purely resistive load of $50 \Omega$. The time taken for the current to rise from half of the peak value to the peak value is:

For an RLC circuit driven with voltage of amplitude $V_{m}$ and frequency $\omega_{0}=\frac{1}{\sqrt{\mathrm{LC}}}$ the current exhibits resonance the quality factor, $Q$ is given by

An alternating voltage $\mathrm{V}=\mathrm{V}_{0} \sin \omega \mathrm{t}$ is applied across a circuit. As a result, a current $\mathrm{I}=\mathrm{I}_{0} \sin \left(\omega \mathrm{t}-\frac{\pi}{2}\right)$ flows in it.…

In series combination of $R, L$ and $C$ with an A.C. source at resonance, if $\mathrm{R}=20 \mathrm{ohm},$ then impedence $Z$ of the combination is

A direct current of $5 \mathrm{~A}$ is superposed on an alternating current $I=10 \sin \omega t$ flowing through the wire. The effective value of the resulting current will be

Voltage $V$ and current $i$ in $A C$ circuit are given by $\mathrm{V}=50 \sin (50 \mathrm{t})$ volt, $\mathrm{i}=50 \sin \left(50 \mathrm{t}+\frac{\pi}{3}\right) \mathrm{mA}$ The power dissipated in the circuit is

The impedance of a circuit consists of $3 \Omega$ resistance and $4 \Omega$ reactance. The power factor of the circuit is

A resistance $\mathrm{R}$ and inductance $\mathrm{L}$ and a capacitor $\mathrm{C}$ all are connected in series with an AC supply. The resistance of $\mathrm{R}$ is 16 ohm and for a given frequency, the inductive…

An alternating voltage $V=V_{0}$ sin ot is appliedacross a circuit. As a result, a current $I=I_{0} \sin (\omega t-\pi / 2)$ flows in it. The power consumed per cycle is

A coil has resistance 30 ohm and inductive reactance 20 ohm at $50 \mathrm{~Hz}$ frequency. If an ac source, of 200 volt, $100 \mathrm{~Hz},$ is connected across the coil, the current in the coil will be

The instantaneous current from an a.c. source is $\mathrm{I}=6 \sin 314 \mathrm{t}$. What is the rms value of the current?