All 24 MCQs of 9th Class Physics Chapter 8, Magnetism, with answers and the reason each option is right or wrong: the 8 textbook exercise MCQs plus 16 more board-style MCQs. Punjab Board new syllabus.
Try each one first: tap an option to check it, then read the reasoning and why the others are wrong.
A note about the questions
The wording follows published solved exercises and every answer was re-checked by hand, so the wording or the order of options may differ slightly from your print.
Answered 0 of 24 · Correct 0
Set A: Textbook exercise 8 MCQs
The multiple-choice questions at the end of Chapter 8 in your book, in the book's option order.
Q8.1Magnetic Materials and Properties of Magnets
Which one of the following is not a magnetic material?
Answer(c) aluminium
Step by step
Magnetic materials: iron, nickel, cobalt (and steel).
Aluminium is not pulled by an ordinary magnet.
Why the others are wrong
(a) cobalt is a magnetic material.
(b) iron is the most common magnetic material.
(d) nickel is a magnetic material.
Remember
The magnetic three: iron, nickel, cobalt.
Q8.2Magnetic Field
Magnetic lines of force:
Answer(d) enter into the south pole
Step by step
Lines leave N and curve round to S.
They never cross, because the field has only one direction at a point.
Why the others are wrong
(a) they are curved round a bar magnet.
(b) lines of force never cross.
(c) they leave the north pole.
Remember
Out of North, into South.
Q8.3Magnetic Materials and Properties of Magnets
Permanent magnets cannot be made by:
Answer(a) soft iron
Step by step
Soft iron: domains line up easily and fall back easily.
Steel, alnico and neodymium keep their alignment: permanent magnets.
Why the others are wrong
(b) steel is used for permanent magnets.
(c) neodymium alloy makes very strong permanent magnets.
(d) alnico (aluminium-nickel-cobalt) is a permanent-magnet alloy.
Remember
Soft iron = temporary.
Q8.4Uses of Magnets and Electromagnets
Permanent magnets are used in:
Answer(b) loudspeaker
Step by step
Circuit breaker, crane, recording head: need magnetism that can be switched, so electromagnets.
Loudspeaker: the voice coil moves in the field of a permanent magnet.
Why the others are wrong
(a) a circuit breaker uses an electromagnet.
(c) a crane must drop its load, so it uses an electromagnet.
(d) the recording head is an electromagnet.
Remember
Switched on and off = electromagnet; always on = permanent.
Q8.5Magnetisation and Demagnetisation
A common method used to magnetise a material is:
Answer(a) stroking
Step by step
Magnetising: stroking, or a solenoid carrying D.C.
Demagnetising: heating, hammering, or a solenoid carrying A.C.
Why the others are wrong
(b) hitting (hammering) demagnetises.
(c) heating demagnetises.
(d) A.C. reverses the field again and again, so it demagnetises.
Remember
D.C. makes a magnet; A.C. unmakes it.
Q8.6Magnetic Field
A magnetic compass is placed at four points around a bar magnet whose N-pole is on the left and S-pole on the right: just left of N, just right of S, above the middle and below the middle. Which set of needle directions (left of N, right of S, above, below) is correct?
Answer(c) left, left, right, right
Step by step
Left of the N-pole: the field points away from N, so left.
Right of the S-pole: the field points into S, so left again.
Above and below the middle: lines run from N to S, so right in both places.
Why the others are wrong
(a) right of the S-pole the field goes into S (left), and below the magnet it runs N to S (right).
(b) above the magnet the field runs from N to S, which is to the right.
(d) the needle right of S must point into S, and both sides must point from N to S.
Remember
At both ends the needle points the same way; along the sides it points the other way.
Q8.7Magnetisation and Demagnetisation
A steel bar AB is magnetised by the double-touch method: starting at the centre, the S-pole of one magnet is stroked towards end A and the N-pole of another towards end B. What will be the polarity of the bar?
Answer(a) A becomes N and B becomes S
Step by step
Rule: the end where a stroke finishes gets the opposite pole to the stroking pole.
S strokes towards A, so A is N.
N strokes towards B, so B is S.
Why the others are wrong
(b) that gives each end the same polarity as its stroking pole.
(c) unlike poles stroke the two halves, so the bar becomes one simple magnet.
(d) the same mistake the other way round.
Remember
Stroke with S, get N at the end.
Q8.8Uses of Magnets and Electromagnets
The best material to protect a device from an external magnetic field is:
Answer(d) soft iron
Step by step
Wood and plastic let the field straight through.
Soft iron draws the field lines into itself, leaving the inside nearly field-free.
Why the others are wrong
(a) wood is non-magnetic; the field passes straight through.
(b) plastic is non-magnetic.
(c) steel is magnetic but its permeability is lower, and it can become a magnet itself.
Remember
Magnetic shield = soft iron.
Set B: More MCQs from this chapter 16 MCQs
Extra questions on the same ideas, of the kind set in board papers and class tests.
QB1Magnetic Materials and Properties of Magnets
A freely suspended bar magnet comes to rest pointing:
Answer(b) north-south
Step by step
The Earth behaves like a huge magnet.
A free magnet turns until it lies north-south.
Why the others are wrong
(a) it comes to rest north-south.
(c) a horizontally hung magnet stays horizontal.
(d) it always settles in the same direction.
Remember
This is how a compass works.
QB2Magnetic Materials and Properties of Magnets
The real test to identify a magnet is:
Answer(b) repulsion
Step by step
Attraction: could be a magnet or just a magnetic material.
Repulsion: only between like poles of two magnets.
Why the others are wrong
(a) plain iron is attracted too.
(c) weight tells nothing about magnetism.
(d) colour tells nothing.
Remember
Only a magnet can be repelled.
QB3Magnetic Materials and Properties of Magnets
A bar magnet is broken into two pieces. Each piece will:
Answer(c) be a complete magnet with an N-pole and an S-pole
Step by step
Each tiny domain is a complete magnet.
So any piece, however small, has both poles.
Why the others are wrong
(a) a single N-pole cannot exist.
(b) a single S-pole cannot exist.
(d) the pieces stay magnetised.
Remember
No magnet has only one pole.
QB4Magnetic Field
The direction of the magnetic field at a point is the direction in which:
Answer(b) the N-pole of a compass needle points
Step by step
Place a small compass at the point.
Its N-pole points along the field.
Why the others are wrong
(a) the S-pole points opposite to the field.
(c) filings show the pattern, not the direction.
(d) moving the magnet is not the definition.
Remember
Follow the N of the compass.
QB5Magnetic Field
Around a bar magnet, the magnetic field is strongest:
Answer(b) near the poles
Step by step
Field strength ∝ number of lines through unit area.
Lines are closest together at the poles.
Why the others are wrong
(a) the field is weakest beside the middle.
(c) far away the lines are spread out.
(d) it varies from place to place.
Remember
Crowded lines = strong field.
QB6Magnetic Field
A neutral point between two magnets is a point where:
Answer(b) the fields of the two magnets cancel each other
Step by step
Put like poles facing each other.
Midway, the two fields are equal and opposite: the net field is zero.
Why the others are wrong
(a) it is where the field is zero.
(c) lines of force never cross.
(d) there is no pole there.
Remember
Neutral = cancelled.
QB7Uses of Magnets and Electromagnets
The core of an electromagnet is made of soft iron because soft iron:
Answer(b) is magnetised strongly when the current flows and loses it when the current stops
Step by step
An electromagnet must be switchable.
Soft iron gains and loses magnetism easily.
Why the others are wrong
(a) a permanent core would not switch off.
(c) soft iron is strongly magnetic.
(d) cost is not the reason.
Remember
Switch on, magnet; switch off, no magnet.
QB8Uses of Magnets and Electromagnets
The strength of an electromagnet can be increased by:
Answer(b) increasing the number of turns of the coil
Step by step
Each turn adds its field.
So more turns or more current give a stronger magnet.
Why the others are wrong
(a) less current makes it weaker.
(c) wood is non-magnetic; it would weaken it.
(d) reversing only swaps the poles.
Remember
More turns, more current.
QB9Magnetisation and Demagnetisation
By the right-hand grip rule for a solenoid, when the fingers curl in the direction of the current, the thumb points towards the:
Answer(b) N-pole
Step by step
Curl the right-hand fingers in the direction of the current in the turns.
