Alternating Current

A capacitor of capacitance ' C ' is connected across a.c. source of voltage V as $\mathrm{V}=\mathrm{V}_0 \sin \omega \mathrm{t}$. The displacement current between the plates of the capacitor would be

In an a.c. circuit $I=50 \sin 100 \pi t$. The time required for the current to achieve its peak value will be

An inductor of 0.5 mH , capacitor of $20 \mu \mathrm{~F}$ and resistance of $20 \Omega$ are connected in series with a 220 V a.c. source. If the current is in phase with e.m.f., the maximum current in the circuit is $\sqrt{x} A$. The value ...

An alternating voltage $\mathrm{V}=100 \sqrt{2} \sin (50 \mathrm{t})$ is connected to $2 \mu \mathrm{~F}$ capacitor through a.c. ammeter. The reading of the ammeter is

Out of the following graphs, the correct graphical relation for LC parallel resonant circuit at resonance is

The frequency of oscillation of LCR series circuit is ' $F$ '. The value of capacitance is tripled, then new frequency becomes ' xF '. The value of ' $x$ ' is

The instantaneous value of current in an a.c. circuit is $I=2 \sin \left[100 \pi t+\frac{\pi}{3}\right]$ A. The current will be maximum for the first time at $\left(\sin 90^{\circ}=1\right)$

The resistance of a coil for d.c. is $5 \Omega$. In a.c., the resistance will

In an oscillating LC circuit, the maximum charge on the capacitor is ' $Q$ '. When the energy is stored equally between the electric and magnetic fields, the instantaneous charge on the capacitor ' $q$ ' is

In the series LCR circuit shown in figure, the impedance is

A resistor of $400 \Omega$, an inductance of 0.4 H are in series with an a.c. source of e.m.f. $\mathrm{E}=200 \sqrt{2} \sin (1000 \mathrm{t})$. The power factor of the circuit is

An alternating current is given by $\mathrm{I}=100 \sin (50 \pi t)$. How many times will the current become zero in one second?