Question 1 :
In a transformer, the number of turns of primary coil and secondary coil are $$5$$and$$4$$respectively. If$$220 V$$isapplied on the primary coil, then the ratioof primary current to the secondary current is
Question 2 :
The correct formula for the angular frequency $$\omega_0$$ of an $$L-C$$ resonant circuit is
Question 4 :
$$Transformer \rightarrow ideal \rightarrow E_{P} = 1000\ V, I_{P} = 50A$$<br>$$220V \rightarrow 80\ houses$$<br>Resistance of secondary coil will be
Question 5 :
If the resistance in a parallel resonant circuit is reduced, the bandwidth:
Question 6 :
A transformer having $$4000$$ turns on its primary side and $$500$$ turns on the secondary side. If the input voltage is $$240\ V$$, find out the output voltage of the secondary side of the transformer ?
Question 7 :
The self inductance of the motor of an electric fan is 10 H. In order to impart maximum powr of 50 Hz, it should be connected to a capacitance of<br>
Question 8 :
In an ac circuit with voltage V and current I, the power dissipated is
Question 9 :
For L-C-R, A.C circuit resonance frequency is $$600Hz$$ and frequencies at half power points are $$550Hz$$ and $$650Hz$$. What will be the Q-factor?
Question 10 :
A device that increases the voltage of an alternating current is called a(n)
Question 11 :
On connecting a condenserin parallel to an electricfanconnected to an AC circuit, the phase angle
Question 13 :
A 220V, 50Hz a.c. generator is connected to an inductor and a 50$$\Omega $$ resistance in series. The current in the circuit is 1.0A. The P.D. across the inductor is:<br/>
Question 14 :
In an LCR series circuit, the capacitor is changed from C to 4C. For the same resonant frequency, the inductance should be changed from L to<br/>
Question 15 :
The number of turns in the coil of an AC generator is 5000 and the area of the coil is$$0.25 \ m^2.$$ The coil is rotated at the rate of 100 cycles /sec in the magnetic field of $$0.2 W/m^2$$. then the peak value will be :
Question 16 :
The ratio of turns in the transformer is given as 2:3. If the current passing through the primary coil is 3 A. Find the current through the load resistance:
Question 17 :
An LCR circuit is connected to a source of alternating current. At resonance, the applied voltage and the current flowing through the circuit will have a phase difference of <br/>
Question 19 :
A200 km long wire has a capacity of $$0.01\ \mu F$$ per km.Ifit carries an alternating current of frequency $$50\ Hz,$$ theinductance to be connected in series so that theimpedanceis minimum is approximately,
Question 20 :
The coefficient of induction of a choke coil is $$ 0.1\,H $$ and resistance is $$12 \Omega $$ . If it is connected to an alternating current source offrequency $$ 60 \,Hz $$ , then power factor will be
Question 21 :
Rms value of current$$i = 3 + 4\sin \left( {\omega t + \frac{\pi }{3}} \right)$$ is:
Question 22 :
Which of the following combination should be selected for better turning of an L.C.R circuit used for communication?
Question 23 :
In an L-R circuit, the voltage is given by $$V$$ as $$283 sin 314t$$. The current is found tc be $$4 \, sin \left ( 314t-\dfrac {\pi}{4} \right )$$Calculate the resistance of the circuit. 
Question 24 :
An AC source of variable frequency is appliedacross a series L-C-R circuit. At a frequencydouble the resonance frequency, the impedanceis $$\sqrt{10}$$ times the minimum impedance. Theinductive reactance is<br>
Question 25 :
In an $$AC$$ circuit, the voltage is given by $$V = 110  sin  2\pi (60) t $$.The voltage across the inductor, capacitor as well as resistor:
Question 26 :
Net impedance of an series $$LCR$$ ac circuit at half power frequency will be :-
Question 27 :
If the total charge stored in the LC circuit is $$\mathrm{Q}_{0}$$, then for $$\mathrm{t}\geq 0$$<br/>
Question 28 :
If resistance is removed from the circuit and the value of inductance is doubled, the variation of current with time in the new circuit is:
Question 29 :
Assertion: In series $$LCR$$ circuit if a ferromagnetic rod is inserted inside an inductor, current in the circuit may be increase or decrease.
Reason: By doing so $$X_L$$ will increase.
Question 30 :
An alternating current of $$1.5mA$$ and angular frequency $$300\ rad/sec$$ flows through a $$10K\Omega$$ resistor and a $$0.50\mu F$$ capacitor in series. find the rms voltage across the capacitor and impedance of the circuit?
