Alternating Current

In a circuit containing a pure resistor connected to an AC source,

A light bulb rated $100$ W is connected to an AC source of $220$ V, $50$ Hz. The rms current through the bulb is

A small town with a demand of $900\text{ kW}$ of electric power at $220\text{ V}$ is situated $20\text{ km}$ away from an electric power generating station. Each wire of the two-wire transmission line has a resistance per unit length of $5 ...

A series LCR circuit containing an AC source of 100 V has an inductor and a capacitor of reactances $24 \Omega$ and $16 \Omega$ respectively. If a resistance of $6 \Omega$ is connected in series, then the potential difference across the ser...

A sinusoidal voltage produced by an AC generator at any instant t is given by an equation $\mathrm{V}=311 \sin 314$ t. The rms value of voltage and frequency are respectively

In domestic electric mains supply, the voltage and the current are

In an $L-C-R$ series circuit, the value of only capacitance $C$ is varied. The resulting variation of resonance frequency $f_0$ as a function of $C$ can be represented as

The figure shows variation of $R, X_L$ and $X_C$ with frequency $f$ in a series $L-C-R$ circuit. Then, for what frequency point is the circuit capacitive?

Which of the following combinations should be selected for better tuning of an $L-C-R$ circuit used for communication?

An ideal transformer has a turns ratio of 10. When the primary is connected to \(220 \mathrm{~V}, 50 \mathrm{~Hz}\) as source, the power output is

In series \(L C R\) circuit at resonance, the phase difference between voltage and current is

Total impedance of a series \(L\)-\(C\)-\(R\) circuit varies with angular frequency of the \(\mathrm{AC}\) source connected to it as shown in the graph. The quality factor \(Q\) of the series \(L\)-\(C\)-\(R\) circuit 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 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

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

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

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

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

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?

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

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

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?

Which of the following, represents the variation of inductive reactance $\left(X_L\right)$ with the frequency of voltage sources $(v)$ ?

A 100 W bulb is connected to an AC source of $220 \mathrm{~V}, 50 \mathrm{~Hz}$. Then, the current flowing through the bulb is

In Karnataka, the normal domestic power supply AC is $220 \mathrm{~V}, 50 \mathrm{~Hz}$. Here, 220 V and 50 Hz refer to

In the series $L-C-R$ circuit, the power dissipation is through

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

A coil of inductive reactance $1 / \sqrt{3} \Omega$ and resistance $1 \Omega$ is connected to a $200 \mathrm{~V}, 50 \mathrm{~Hz}$ AC supply. The time lag between maximum voltage and current is

The output of a step down transformers is measured to be 48 V when connected to a 12 W bulb. The value of peak current is