A 25eV electron has a speed of
1.2 x 106m/sec
2.3 x 106m/sec
3.5 x 106m/sec
4.4 x 106m/sec
Posted Date:-2021-08-29 22:45:37
A 5 ?F capacitor has a potential difference across its plates of 200 volts. The charge on the capacitor is
1.2.5 x 10-8 C
2.10-5 C
3.103 C
4.4 x 103 C
Posted Date:-2021-08-29 22:45:37
A capacitor is a perfect insulator for
1.direct current
2.alternating current
3.both for the direct and alternating current
4.none of above
Posted Date:-2021-08-29 22:45:37
A charge of 0.10C accelerated through a potential difference of 1000V acquires kinetic energy
1.200J
2.100J
3.1000J
4.100 eV
Posted Date:-2021-08-29 22:45:37
A dynamo converts
1.mechanical energy into electrical energy
2.electrical energy into mechanical energy
3.magnetic energy into mechanical energy
4.magnetic energy into electrical energy
Posted Date:-2021-08-29 22:45:37
A.C and D.C have the same
1.effect in charging a capacitor
2.effect in charging a battery
3.effect while passing through an inductance
4.heating effect through a resistance
Posted Date:-2021-08-29 22:45:37
A.C cannot be used for
1.producing heat
2.producing light
3.magnetizing and electroplating
4.all the above
Posted Date:-2021-08-29 22:45:37
An alternating current or voltage
1.fluctuates off and on
2.varies in magnitude alone
3.changes its direction again and again
4.changes its magnitude continuously and reverses its direction of flow after regularly recurring intervals.
Posted Date:-2021-08-29 22:45:37
capacitor is to have an energy content of 20J it must be placed across a potential difference of
1.4 volts
2.9 volts
3.2 volts
4.1 vol
Posted Date:-2021-08-29 22:45:37
cmf generated by A.C dynamo depends upon
1.number of turns in the coil
2.magnetic field strength
3.frequency of rotation
4.all of above
Posted Date:-2021-08-29 22:45:37
Current produced by moving the loop of wire across a magnetic field is called
1.A.C current
2.D.C current
3.induced current
4.mean square current
Posted Date:-2021-08-29 22:45:37
Electric field due to positive charged plate is E = ?/2??. If oppositely charged plate of same amount is placed parallel to it, then resultant field contains amount of energy
1.Q/?oA
2.Q/e
3.QV2
4.Q2/C
Posted Date:-2021-08-29 22:45:37
Electric flux due to a point charge +q is
1.1/4II?? . q/r
2.q/??
3.1/4II?? . q/r2
4.4II??
Posted Date:-2021-08-29 22:45:37
Electric intensity at infinite distance from the point charge is
1.zero
2.infinite
3.positive
4.negative
Posted Date:-2021-08-29 22:45:37
emf induced in a circuit according to Faradays law depends on the
1.maximum magnetic flux
2.rate of change of magnetic flux
3.change in magnetic flux
4.initial magnetic flux
Posted Date:-2021-08-29 22:45:37
Energy stored in a magnetic field is given by
1.LI2
2.L2I/2
3.LI2/2
4.IL2
Posted Date:-2021-08-29 22:45:37
Equipotential planes are
1.parallel to one another
2.non parallel to one another
3.intersecting
4.circular
Posted Date:-2021-08-29 22:45:37
Equivalent capacitance is greater than individual capacitances in
1.series combination
2.parallel combination
3.both series and parallel combinations
4.none of above
Posted Date:-2021-08-29 22:45:37
For electroplating we use
1.A D.C source
2.an A.C source
3.any source
4.all of the above
Posted Date:-2021-08-29 22:45:37
For what value of ? the electric flux has average value of those of extreme values ?
1.60?
2.45?
3.90?
4.0?
Posted Date:-2021-08-29 22:45:37
If a charged rod is brought closer to a gas filled balloon then
1.Radius decreases
2.Balloon bursts
3.Radius increase
4.Balloon squeezes
Posted Date:-2021-08-29 22:45:37
If an electrons is allowed to move along the field in a non uniform electric field then it will follow
1.Spiral path
2.Straight line
3.Curved path
4.Circular path
Posted Date:-2021-08-29 22:45:37
If metallic conductor is charged negatively then its weight
1.Remains same
2.First increases then decreases
3.Decreases then increases
4.Increases for a while
Posted Date:-2021-08-29 22:45:37
If mica sheet is placed between the plates of a capacitor the capacity
1.increases
2.decreases
3.increases then decreases
4.decreases then increases
Posted Date:-2021-08-29 22:45:37
If the coil is wound on an iron core the flux through it will
1.decrease
2.become zero
3.remain the same
4.increase
Posted Date:-2021-08-29 22:45:37
If the secondary coil has Ns turns and the primary Np turns the relation between secondary and primary voltages is given by
1.Vs/Vp = Np/Ns
2.Vs/Vp = Ns/Np
3.Vp/Vs = Ns/Np
4.Vp/Vs = Np/Ns
Posted Date:-2021-08-29 22:45:37
If two charges are increased by two times then force
1.Decreases 9 times
2.Increases 9 times
3.Increases 4 times
4.Decreases 4 times
Posted Date:-2021-08-29 22:45:37
In a charged capacitor the energy resides in
1.magnetic hield
2.electric field
3.nuclear field
4.gravitational field
Posted Date:-2021-08-29 22:45:37
In a non-uniform electric field a polar molecule will experience
1.Net torque
2.Net force
3.both series and parallel combinations
4.zero
Posted Date:-2021-08-29 22:45:37
Inductors acts as a short circuit for
1.AC
2.DC
3.Both (a) and (b)
4.none of these
Posted Date:-2021-08-29 22:45:37
N/C =
1.V/A
2.J/V
3.V/m
4.A/m
Posted Date:-2021-08-29 22:45:37
Photocopier and inject printer are dealt in
1.Electrostatics
2.Charges in motion
3.Capacitors
4.Electric fields
Posted Date:-2021-08-29 22:45:37
Potential difference is the work done in moving unit positive charge form one point to another
1.in the direction of electric intensity
2.against electric intensity
3.in any direction
4.in the direction of electric flux
Posted Date:-2021-08-29 22:45:37
Power loss in actual transformer is due to
1.Small output
2.Eddy currents and magnetic hysterias
3.Soft iron core
4.Back emf
Posted Date:-2021-08-29 22:45:37
Selenium becomes a conductor in light so it behaves like
1.Semiconductor
2.Photodiode
3.Light emitting diode
4.Capacitor
Posted Date:-2021-08-29 22:45:37
Self inductance of a coil depends upon
1.current flowing
2.number of turns per unit length
3.voltage produce
4.all
Posted Date:-2021-08-29 22:45:37
SI unit of permitivity of free space is
1.Nm2C2
2.N-1mC-2
3.NmC-1
4.N-1m-2C2
Posted Date:-2021-08-29 22:45:37
The number of electrons in one coulomb charge is equal to
1.6.2 x 1018
2.1.6 x 1019
3.6.2 x 1021
4.1.6 x 10-27
Posted Date:-2021-08-29 22:45:37
The only difference between construction of D.C generator and A.C generator is that of
1.carbon brushes
2.coil
3.commutator
4.magnetic field
Posted Date:-2021-08-29 22:45:37
The practical illustration of the phenomenon of mutual induction is
1.A.C generator
2.D.C dynamo
3.induction coil
4.transformer
Posted Date:-2021-08-29 22:45:37
The value of the capacitance depends upon the
1.voltage applied
2.thickness of the capacitor plates
3.geometry of the capacitor
4.dinsity of the capacitor plates
Posted Date:-2021-08-29 22:45:37
Three capacitors C1 C2 and C3 are connected in parallel as in the Fig. The equivalent capacitance will be
1.8?F
2.0.8?F
3.1?F
4.16?F
Posted Date:-2021-08-29 22:45:37
Two oppositely charged balls A and B attract third conducting ball C when placed near them turn by turn. Then ball C must be
1.positively charged
2.electrically neutral
3.negatively charged
4.positively and negatively charged
Posted Date:-2021-08-29 22:45:37
Value of ?r for various dielectrics is always
1.less than unity
2.equal to unit
3.larger than unit
4.no hard and fast rule
Posted Date:-2021-08-29 22:45:37
Weber is the unit of
1.Magnetic field intensity
2.magnetic induction
3.magnetic flux
4.self-inductance
Posted Date:-2021-08-29 22:45:37
Which of the following uses electric energy and does not convert it into any other form?
1.transformer
2.motor
3.D.C generator
4.A.C generator
Posted Date:-2021-08-29 22:45:37
Which of the following works on torque on the current carrying conductor placed in magnetic field.
1.galvanometer
2.ammeter
3.voltmeter
4.all of the above
Posted Date:-2021-08-29 22:45:37
Which one of the following can be taken as the measure of electric intensity ?
1.F/A
2.?/A
3.???/A
4.q/??A
Posted Date:-2021-08-29 22:45:37
Which one of the following functions like a motor?
1.galvanometer
2.ammeter
3.voltmeter
4.all of above
Posted Date:-2021-08-29 22:45:37
Work done in moving a point charge from one point to another point of equipotential surface is
1.?W = 1?V
2.?W = F?r
3.zero
4.W = 1/4????V
Posted Date:-2021-08-29 22:45:37