Question 1 :
A metallic sphere of radius $18cm$ has been given a charge of $5\times { 10 }^{ -6 }C$. The energy of the charged conductor is :
Question 2 :
A parallel plate capacitor of $1\mu F$ capacity is discharging through a resister. If its energy reduces to half in one second. The value of resistance will be?
Question 3 :
A capacitor of capacity C$_{1}$ charged up to V volt and then connected to an uncharged capacitor C$_{2}$.Then final P.D. across each will be:
Question 4 :
A $2 \mu F$ capacitor is charged to $100 V$ and then its plates are connected by a conducting wire, the heat produced is :
Question 5 :
The capacity of a condenser is $4 \times 10^{-6}$ farad and its potential is 100 volts. The energy released on discharging it fully will be
Question 6 :
The capacity of a condenser is 20$\mu F$ $\displaystyle $ and the potential is 20 V. The energy released an discharging it fully will be
Question 7 :
If a capacitor having capacitance of $1200\mu F$ is charged at a uniform rate of $100\mu C/s$, what is the time required to increase its potential by $20$ volts?
Question 8 :
Two parallel-plate of capacitor have charges +Q and -Q and potential difference $\triangle V$ due to charging, Now the capacitor is disconnected then the potential difference and the stored electrical potential energy is:
Question 9 :
A 16 pF capacitor is connected to 70 V supply. The amount of electric energy stored in the capacitor is:
Question 10 :
The capacitance of a variable capacitor joined with the battery of $100$V is changed from $2\mu F$ to $10\mu F$. What is the change in the energy stored in it?
Question 11 :
An e.m.f. is produced in a coil, which is not connected to an external voltage source. This can be due to
Question 12 :
A helicopter rises vertically with a speed of 100 m/s. If helicopter has length 10 m and horizontal component of earth's magnetic field is $5\times 10^{-3} Wb/m^2$, then the induced emf between the tip of nose and tail of helicopter is:
Question 15 :
A moving conductor coil produces an induced em.f. This is in accordance with<br>
Question 16 :
A straight line conductor of length $0.4\ m$ is moved with a speed of $7\ m/s$ perpendicular to a magnetic filed of intensity $0.9\, Wb/m^2$. The induced e.m.f. across the conductor is
Question 17 :
If circular coil with $N_{1}$ turns is changed in to a coil of $N_{2}$ turns. What will be the ratio of self inductances in both cases.
Question 18 :
Foran inductorcoil $L = 0.04H$ then work done by source to establish a current of 5A in it is:-
Question 21 :
An inductance, a capacitance and a resistance are connected in series across a source of alternating voltages. At resonance, the applied voltage and the current flowing through the circuit will have a phase difference of<br/>
Question 23 :
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 25 :
If the resistance in a parallel resonant circuit is reduced, the bandwidth:
Question 26 :
A transformer with a $110 V$ primary has a $15:1$ turns ratio. The load resistance, $R_L$, is $120$ . What is the approximate voltage across the load?<br/>
Question 27 :
$Transformer \rightarrow ideal \rightarrow E_{P} = 1000\ V, I_{P} = 50A$<br>$220V \rightarrow 80\ houses$<br>Resistance of secondary coil will be
Question 28 :
A step-up transformer of turns ratio $2 : 1$has$50 Hz$ <br> $AC$voltage applied to primary. The frequencyof$AC$output voltage across secondary is
Question 29 :
In a transformer, the number of turns of primary coiland secondary coil are 5 and 4 respectively. If 220V is applied on the primary coil, then the ratio ofprimary current to the secondary current is :
Question 30 :
In a circuit $LC = 10^{-3}H, C = 10^{-3} F$. Find angular frequency.<br/>
Question 32 :
In ballistic galvanometer, the frame on which the coil is wound is non-metallic to:
Question 34 :
A rectangular loop carrying a current $i$ is placed in a uniform magnetic field $B$. The area enclosed by the loop is $A$. If there are $n$ turns in the loop, the torque acting on the loop is given by<br/>
Question 35 :
Which rule is used to find the direction of magnetic field in a toroid?
Question 36 :
If the current is doubled, the deflection is also doubled in
Question 38 :
The current that must flow through the coil of a galvanometer so as to produce a deflection of one division on its scale is called<br>
Question 39 :
The time period of a charged particle undergoing a circular motion in a uniform magnetic field is independent of its
Question 40 :
In a current-carrying solenoid, the magnetic field direction is given by the right hand rule such that the
Question 41 :
A parallel plate capacitor is charged and then disconnected from the source of potential difference. If the plates of the condenser are then moved farther apart by the use of an insulated handle, which one of the following is true?<br/>
Question 43 :
The smallest resistance that can be obtained by combining 10 resistors each of resistance $10 \Omega$is
Question 46 :
Three resistors each having same resistance are connected in parallel. Their equivalent resistance is$\displaystyle 5\Omega$. If they are connected in series, their equivalent resistance is.
Question 47 :
State whether given statement is True or False<br/>The sum of all the voltage drops around a single closed loop in a circuit is zero.
Question 48 :
When a 1 ohm resistor is connected across the potential difference of 20 V, what will be power dissipation in it?
Question 49 :
A wire of uniform cross-section has a resistance of $R \ \ \Omega$. What would be the resistance of a similar wire, made of the same material, but twice as long and of twice the diameter?
Question 50 :
For a heater rated at4.4 kW; 220 V. Calculatethe current drawn by the heater.
