Alternating Current · Physics · KCET
MCQ (Single Correct Answer)
Which of the following combinations should be selected for better tuning of an $L-C-R$ circuit used for communication?
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?
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
In series $$L C R$$ circuit at resonance, the phase difference between voltage and current is
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 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 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
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
An alternating current is given by $$i=i_1 \sin \omega t+i_2 \cos \omega t$$. The rms current is given by
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
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?
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