Alternating Current - Electromagnetism - Physics Previous Year Questions

In the A.C. circuit shown, keeping ' $K$ ' pressed, if an iron rod inserted into the coil, the bulb in the circuit,

The frequency of an alternating current is \(50 \mathrm{~Hz}\). What is the minimum time taken by current to reach its peak value from rms value?

An inductor of inductance \(L\) and resistor \(R\) are joined together in series and connected by a source of frequency \(\omega\). The power dissipated in the circuit is

In the given circuit the peak voltage across \(C, L\) and \(R\) are \(30 \mathrm{~V}, 110 \mathrm{~V}\) and \(60 \mathrm{~V}\), respectively. The rms value of the applied voltage is

The power factor of \(R-L\) circuit is \(\frac{1}{\sqrt{3}}\). If the inductive reactance is \(2 \Omega\). The value of resistance is

In the given circuit, the resonant frequency is

A \(220 \mathrm{~V}\) AC supply is connected between points \(A\) and \(B\) as shown in figure, what will be the potential difference \(V\) across the capacitor?

In an oscillating \(L C\)-circuit, \(L=3 \mathrm{mH}\) and \(C=2.7 \mu \mathrm{F}\). At \(t=0\), the charge on the capacitor is zero and the current is \(2 \mathrm{~A}\). The maximum charge that will appear on the capacitor will be

What will be the reading in the voltmeter and ammeter of the circuit shown?

LC-oscillations are similar and analogous to the mechanical oscillations of a block attached to a spring. The electrical equivalent of the force constant of the spring is

An alternating current is given by \(i=i_1 \sin \omega t+i_2 \cos \omega t\). The rms current is given by

A series resonant \(\mathrm{AC}\) circuit contains a capacitance \(10^{-6} \mathrm{~F}\) and an inductor of \(10^{-4} \mathrm{H}\). The frequency of electrical oscillations will be

In a series \(L C R\) circuit, \(R=300 \Omega, L=0.9 \mathrm{H}, C=2.0 \mu \mathrm{F}\) and \(\omega=1000 \mathrm{~rad} / \mathrm{s}\), then impedance of the circuit is

A fully charged capacitor \(C\) with initial charge \(q_0\) is connected to a coil of self inductance \(L\) at \(t=0\). The time at which the energy is stored equally between the electric and the magnetic field is