laboursonline – MCQs, Mock Tests | MCAT MCAT Physics Mcq Questions Electromagnetic Induction

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

✅ Correct Answer: 2

Equipotential planes are

1. parallel to one another
2. non parallel to one another
3. intersecting
4. circular

✅ Correct Answer: 1

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

✅ Correct Answer: 3

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

✅ Correct Answer: 2

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

✅ Correct Answer: 2

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

✅ Correct Answer: 3

Equivalent capacitance is greater than individual capacitances in

1. series combination
2. parallel combination
3. both series and parallel combinations
4. none of above

✅ Correct Answer: 2

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

✅ Correct Answer: 2

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

✅ Correct Answer: 1

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

✅ Correct Answer: 3

SI unit of permitivity of free space is

1. Nm2C2
2. N-1mC-2
3. NmC-1
4. N-1m-2C2

✅ Correct Answer: 4

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

✅ Correct Answer: 3

Electric intensity at infinite distance from the point charge is

1. zero
2. infinite
3. positive
4. negative

✅ Correct Answer: 1

Which one of the following can be taken as the measure of electric intensity ?

1. F/A
2. ?/A
3. ???/A
4. q/??A

✅ Correct Answer: 2

Electric flux due to a point charge +q is

1. 1/4II?? . q/r
2. q/??
3. 1/4II?? . q/r2
4. 4II??

✅ Correct Answer: 2

N/C =

1. V/A
2. J/V
3. V/m
4. A/m

✅ Correct Answer: 3

A charge of 0.10C accelerated through a potential difference of 1000V acquires kinetic energy

1. 200J
2. 100J
3. 1000J
4. 100 eV

✅ Correct Answer: 2

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

✅ Correct Answer: 1

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

✅ Correct Answer: 1

In a charged capacitor the energy resides in

1. magnetic hield
2. electric field
3. nuclear field
4. gravitational field

✅ Correct Answer: 2

For what value of ? the electric flux has average value of those of extreme values ?

1. 60?
2. 45?
3. 90?
4. 0?

✅ Correct Answer: 1

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

✅ Correct Answer: 4

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

✅ Correct Answer: 3

Selenium becomes a conductor in light so it behaves like

1. Semiconductor
2. Photodiode
3. Light emitting diode
4. Capacitor

✅ Correct Answer: 2

Photocopier and inject printer are dealt in

1. Electrostatics
2. Charges in motion
3. Capacitors
4. Electric fields

✅ Correct Answer: 1

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

✅ Correct Answer: 3

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

✅ Correct Answer: 4

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

✅ Correct Answer: 1

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

✅ Correct Answer: 3

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

✅ Correct Answer: 2

The practical illustration of the phenomenon of mutual induction is

1. A.C generator
2. D.C dynamo
3. induction coil
4. transformer

✅ Correct Answer: 4

Weber is the unit of

1. Magnetic field intensity
2. magnetic induction
3. magnetic flux
4. self-inductance

✅ Correct Answer: 3

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

✅ Correct Answer: 3

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

✅ Correct Answer: 2

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

✅ Correct Answer: 4

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.

✅ Correct Answer: 4

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

✅ Correct Answer: 1

Which one of the following functions like a motor?

1. galvanometer
2. ammeter
3. voltmeter
4. all of above

✅ Correct Answer: 4

A.C cannot be used for

1. producing heat
2. producing light
3. magnetizing and electroplating
4. all the above

✅ Correct Answer: 3

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

✅ Correct Answer: 4

Self inductance of a coil depends upon

1. current flowing
2. number of turns per unit length
3. voltage produce
4. all

✅ Correct Answer: 4

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

✅ Correct Answer: 4

Energy stored in a magnetic field is given by

1. LI2
2. L2I/2
3. LI2/2
4. IL2

✅ Correct Answer: 3

Inductors acts as a short circuit for

1. AC
2. DC
3. Both (a) and (b)
4. none of these

✅ Correct Answer: 2

For electroplating we use

1. A D.C source
2. an A.C source
3. any source
4. all of the above

✅ Correct Answer: 1

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

✅ Correct Answer: 1

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

✅ Correct Answer: 3

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

✅ Correct Answer: 4

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

✅ Correct Answer: 2

Power loss in actual transformer is due to

1. Small output
2. Eddy currents and magnetic hysterias
3. Soft iron core
4. Back emf

✅ Correct Answer: 2