Magnetism and Electromagnetism MCQs 2026

Magnetic shielding is used to

1. A Increase magnetic field strength ✓
2. B Generate additional current ✓
3. C Convert AC to DC ✓
4. D Protect sensitive devices from external magnetic fields ✓

The area enclosed in a hysteresis loop represents the

1. A Total magnetic flux ✓
2. B Energy lost as heat per cycle of magnetization ✓
3. C Retentivity of the material ✓
4. D Coercive force ✓

A step-up transformer increases voltage while

1. A Keeping current constant ✓
2. B Increasing current as well ✓
3. C Keeping power output higher than input ✓
4. D Decreasing current proportionally ✓

The SI unit of self-inductance is the

1. A Weber ✓
2. B Tesla ✓
3. C Henry ✓
4. D Farad ✓

Mutual induction occurs when a changing current in one coil induces an EMF in

1. A A neighboring coil ✓
2. B The same coil only ✓
3. C A resistor ✓
4. D A capacitor ✓

Eddy currents are

1. A Currents that flow only in wires ✓
2. B Useful in reducing all energy losses ✓
3. C Induced circulating currents in a conductor due to changing magnetic flux ✓
4. D Currents that flow only in insulators ✓

The EMF induced in a conductor moving through a magnetic field is called

1. A Static EMF ✓
2. B Motional EMF ✓
3. C Back EMF ✓
4. D Thermal EMF ✓

Magnetic field lines around a bar magnet

1. A Never intersect each other ✓
2. B Always intersect at the center ✓
3. C Are parallel straight lines only ✓
4. D Originate and end at the same pole ✓

The angle made by the Earth's magnetic field with the horizontal at a place is called

1. A Declination ✓
2. B Angle of dip (inclination) ✓
3. C Latitude ✓
4. D Longitude ✓

Soft iron is preferred over steel for making electromagnet cores because soft iron

1. A Magnetizes and demagnetizes quickly with low retentivity ✓
2. B Retains magnetism permanently ✓
3. C Has higher electrical resistance ✓
4. D Is a better insulator ✓

The standard frequency of AC mains supply in Pakistan is

1. A 60 Hz ✓
2. B 100 Hz ✓
3. C 25 Hz ✓
4. D 50 Hz ✓

A neutral point near a bar magnet is a location where

1. A Magnetic field is maximum ✓
2. B The magnet's field exactly cancels the Earth's horizontal magnetic field ✓
3. C Only the Earth's field exists undisturbed ✓
4. D Two magnets attract most strongly ✓

The imaginary plane passing through the magnetic north and south poles and a given point is called the

1. A Geographic meridian ✓
2. B Equatorial plane ✓
3. C Magnetic meridian ✓
4. D Neutral plane ✓

The angle between the geographic meridian and the magnetic meridian at a place is called

1. A Magnetic dip ✓
2. B Magnetic latitude ✓
3. C Retentivity ✓
4. D Magnetic declination ✓

Coercivity refers to the

1. A Maximum magnetic flux a material can hold ✓
2. B Ability to conduct current ✓
3. C Retained magnetism after removing the field ✓
4. D Reverse magnetic field required to demagnetize a material completely ✓

Retentivity of a magnetic material refers to its ability to

1. A Retain magnetism after the external field is removed ✓
2. B Resist becoming magnetized ✓
3. C Lose magnetism instantly ✓
4. D Conduct electric current ✓

In a cyclotron, the time period of the charged particle's circular motion is

1. A Dependent on its speed ✓
2. B Dependent on the radius of its path ✓
3. C Independent of its speed and radius ✓
4. D Dependent on its mass only, not charge ✓

The force on a charge q moving with velocity v in a magnetic field B is given by

1. A F = qE ✓
2. B F = qvB sin(theta) ✓
3. C F = BIL ✓
4. D F = q squared v B ✓

The value of the permeability of free space (mu-naught) is approximately

1. A 4 pi times 10 to the power minus 7 tesla-metre per ampere ✓
2. B 8.85 times 10 to the power minus 12 farad per metre ✓
3. C 9 times 10 to the power 9 newton metre squared per coulomb squared ✓
4. D 6.6 times 10 to the power minus 34 joule-second ✓

The unit tesla is equivalent to

1. A One weber per second ✓
2. B One ampere per metre ✓
3. C One henry per second ✓
4. D One weber per square metre ✓

According to Lenz's law, if the north pole of a magnet is pushed towards a coil, the near face of the coil develops a

1. A South pole, attracting the magnet ✓
2. B No pole at all ✓
3. C North pole, opposing the approaching magnet ✓
4. D South pole, but no force ✓

A step-down transformer has

1. A More turns in secondary than primary ✓
2. B Fewer turns in secondary than primary ✓
3. C Equal turns in both coils ✓
4. D No coils at all ✓

The magnetic field inside a long solenoid is given by B = mu-naught times n times I, where n represents

1. A Number of turns per unit length ✓
2. B Total number of turns ✓
3. C Total current ✓
4. D Radius of the solenoid ✓

Like magnetic poles

1. A Attract each other ✓
2. B Have no interaction ✓
3. C Repel each other ✓
4. D Neutralize each other ✓

Ferromagnetism arises due to the presence of

1. A Free electrons only ✓
2. B Ionic bonds ✓
3. C Covalent bonds ✓
4. D Magnetic domains that align in an external field ✓

Oersted's experiment demonstrated that

1. A An electric current produces a magnetic field around it ✓
2. B A magnetic field produces an electric current ✓
3. C Magnets repel electrons ✓
4. D Current has no magnetic effect ✓

The SI unit of magnetic field (flux density) is the

1. A Weber ✓
2. B Ampere-turn ✓
3. C Tesla ✓
4. D Henry ✓

The magnetic field pattern outside a current-carrying solenoid closely resembles that of a

1. A Straight wire ✓
2. B Toroid ✓
3. C Single loop ✓
4. D Bar magnet ✓

The direction of the magnetic field around a straight current-carrying conductor is given by

1. A Fleming's left-hand rule ✓
2. B Right-hand thumb rule ✓
3. C Lenz's law ✓
4. D Fleming's right-hand rule ✓

The Biot-Savart law is used to calculate the

1. A EMF induced in a coil ✓
2. B Force on a moving charge ✓
3. C Resistance of a conductor ✓
4. D Magnetic field due to a small current-carrying element ✓

Ampere's circuital law relates the line integral of magnetic field around a closed loop to the

1. A Voltage across the loop ✓
2. B Magnetic flux through the loop ✓
3. C Current enclosed by the loop ✓
4. D Resistance of the loop ✓

The force on a current-carrying conductor placed in a magnetic field is given by

1. A F = BIL sin(theta) ✓
2. B F = qvB ✓
3. C F = BQ ✓
4. D F = IR ✓

A DC motor converts

1. A Mechanical energy into electrical energy ✓
2. B Heat into mechanical energy ✓
3. C Chemical energy into mechanical energy ✓
4. D Electrical energy into mechanical energy ✓

An AC generator converts

1. A Mechanical energy into electrical energy ✓
2. B Electrical energy into mechanical energy ✓
3. C Chemical energy into electrical energy ✓
4. D Heat energy into electrical energy ✓

Lenz's law states that the direction of induced current always opposes

1. A The magnetic field ✓
2. B The change in magnetic flux that produces it ✓
3. C The resistance of the circuit ✓
4. D The applied voltage ✓

Faraday's law of electromagnetic induction states that induced EMF is proportional to the

1. A Resistance of the coil ✓
2. B Current through the coil ✓
3. C Number of turns only ✓
4. D Rate of change of magnetic flux ✓

The direction of induced current in a generator is given by

1. A Fleming's right-hand rule ✓
2. B Fleming's left-hand rule ✓
3. C Right-hand thumb rule ✓
4. D Ampere's law ✓

The direction of force on a current-carrying conductor in a magnetic field (motor effect) is given by

1. A Fleming's right-hand rule ✓
2. B Lenz's law ✓
3. C Fleming's left-hand rule ✓
4. D Right-hand thumb rule ✓

In a toroid, the magnetic field is mostly confined

1. A Inside the toroidal core ✓
2. B Outside the toroid only ✓
3. C Nowhere, it cancels out ✓
4. D Equally inside and outside ✓

Magnetic flux is defined as the product of magnetic field and

1. A Resistance ✓
2. B Area perpendicular to the field ✓
3. C Current ✓
4. D Voltage ✓

The SI unit of magnetic flux is the

1. A Tesla ✓
2. B Henry ✓
3. C Weber ✓
4. D Ampere-turn ✓

Diamagnetic materials, when placed in a magnetic field, are

1. A Strongly attracted ✓
2. B Strongly repelled and retain magnetism ✓
3. C Attracted weakly ✓
4. D Weakly repelled ✓

Paramagnetic materials are

1. A Weakly attracted by a magnetic field ✓
2. B Strongly repelled by a magnetic field ✓
3. C Unaffected by magnetic fields ✓
4. D Strongly attracted like iron ✓

Ferromagnetic materials such as iron, cobalt, and nickel are

1. A Weakly attracted ✓
2. B Weakly repelled ✓
3. C Strongly attracted by a magnetic field ✓
4. D Unaffected by magnetic fields ✓

Above the Curie temperature, a ferromagnetic material

1. A Becomes superconducting ✓
2. B Loses its ferromagnetism and becomes paramagnetic ✓
3. C Becomes strongly diamagnetic ✓
4. D Melts instantly ✓

Unlike a permanent magnet, an electromagnet's magnetic field can be

1. A Switched on and off by controlling the current ✓
2. B Never changed ✓
3. C Only increased, never decreased ✓
4. D Reversed only by heating ✓

A cyclotron is a device used to

1. A Measure magnetic field strength ✓
2. B Generate AC power ✓
3. C Store electrical energy ✓
4. D Accelerate charged particles to high energies using magnetic and electric fields ✓

The working of a moving coil galvanometer is based on the

1. A Photoelectric effect ✓
2. B Torque experienced by a current-carrying coil in a magnetic field ✓
3. C Thermoelectric effect ✓
4. D Electrolysis ✓

MRI (Magnetic Resonance Imaging) machines primarily rely on

1. A X-rays ✓
2. B Radioactive decay ✓
3. C Strong magnetic fields and radio waves ✓
4. D Ultraviolet radiation ✓

Two parallel conductors carrying current in the same direction will

1. A Repel each other ✓
2. B Attract each other ✓
3. C Show no force ✓
4. D Rotate around each other ✓