In review — free for everyone. While a book is in review you are one of its reviewers: read it, use it, and tell us what is wrong. When the reports settle, the Class 6 pass is ₹999 for the year and this book’s PDF is ₹299.
Every magnet has two ends
Look around the house for anything with a magnet in it. A fridge magnet, the clasp on an old bag, a toy that snaps shut. Every one of them has two ends that behave differently from the rest of it. These two ends are called poles. One is the North pole, the other is the South pole. Wherever there is a magnet, both poles are there with it — a pair that never comes apart.
Break a magnet in half, and you might expect one piece to keep the North pole while the other keeps the South. That never happens. Each new piece grows its own North pole and South pole again, however small the piece is cut.
So how do you know something is truly a magnet, and not just a piece of iron a magnet happens to pull? Not by how hard it pulls — iron is drawn toward either pole of a magnet, every time. A true magnet does something iron never does: bring two magnets’ like poles close together, and they push each other away. That push, not the pull, is the real test.
A magnet always has two poles, and they never separate. The push between two like poles marks a true magnet — iron only ever pulls.
What a magnet pulls, and what it leaves alone
Not everything gets pulled toward a magnet. A material a magnet attracts is called a magnetic material. Iron is the most common one. Nickel and cobalt are two more, along with some metals made by mixing them in. A material a magnet never attracts — wood, plastic, glass, rubber — is called non-magnetic.
You do not need a lab to sort one from the other. A magnet and a handful of things from around the house are enough.
A magnet pulls iron, nickel and cobalt. Shiny does not mean magnetic, and heavy does not mean magnetic — only what a thing is made of decides.
Instead of the school's kit: a lab magnet → a fridge magnet or a magnetic clasp; NCERT’s own test objects → whatever is already in the house.
- Guess before you test — look at each object and decide whether you think the magnet will pull it.
- Test one object at a time by holding the magnet close to it and watching what happens.
- Sort each object into two piles: pulled, and not pulled.
- Compare your two piles with your first guesses, and see which ones surprised you.
Instead of the school's kit: paperclips → safety pins, small nails, or steel washers.
- Hang the first pin off one pole of the magnet.
- Add a second pin to the bottom of the first, then a third to the bottom of that one, and keep going.
- Count how many pins the chain holds before it grows too long and the last one falls off.
- Try again from the magnet’s other pole, and see whether the chain is the same length.
Where a magnet pulls hardest
A magnet does not pull with the same strength everywhere along its length. Scatter fine iron dust or steel pins on a sheet of paper, hold a magnet under it, and tap the paper gently. Most of the dust or pins gather at the two ends — the poles — and only a few stick along the middle.
Two different magnets can also pull with different strength. Counting how many pins each one lifts is one plain way to compare them.
A magnet’s pull is strongest at its two ends and weakest along its middle. Strength you cannot see, you can count.
Instead of the school's kit: iron filings → dust sanded off a rusty nail, or steel sewing pins as a coarser stand-in.
- Scatter the dust or pins over the sheet of paper.
- Slide the magnet under the paper, or lay it flat on top.
- Tap the paper gently a few times.
- Look at where the dust or pins have gathered.
Careful: wash your hands after handling sandpaper dust — do not rub your eyes while your fingers are dusty.
In the school version: using three or four different magnets to lift steel pins or clips, and comparing how many pins each magnet lifts before none more will stick.
The pins were added one at a time, until no more would stick. In one such comparison the flat fridge magnet held 3 pins, the small button magnet 5, and the short bar magnet 9.
Your own magnets will give different numbers, and that is fine. What does not change is that each magnet has its own count, and the counts can be put in order. That order is what stronger means for a magnet — not something you can see by looking at it, only something you can count.
Making a magnet, and finding its ends
An iron sewing needle can be turned into a small magnet without buying anything new. Stroke it with one pole of a magnet you already have, always the same way. After enough strokes, the needle itself starts pulling other iron toward it.
Always stroke the same way, and lift the magnet clear between strokes. Rubbing back and forth undoes what the stroke before it did.
Instead of the school's kit: a permanent bar magnet → a fridge magnet or magnetic clasp; a cork → a foam scrap or a marker-cap slice.
- Hold the needle flat on a table and pick one pole of the magnet.
- Stroke that pole along the needle in one direction only, from one end to the other.
- Lift the magnet clear of the needle before every new stroke, then bring it back to the same starting end.
- Repeat this thirty to forty times, always in the same direction.
- Test the needle by bringing it near a few pins or a little iron dust — it should now pull them toward it.
Careful: hold the needle by its blunt end — the point is sharp.
A magnet can be left free to turn, hung from a thread or floated on water. It always settles pointing the same way, north to south. The end that turns toward north is the magnet’s North pole; the other end is its South pole.
An ordinary iron bar, tested the same way, does not settle in any direction. That is one more way to tell a magnet apart from plain iron.
A magnet left free to turn settles north to south. A plain iron bar does not, and that is one way to tell the two apart.
Instead of the school's kit: a bar magnet → the sewing needle already magnetised by stroking.
- Tie the thread around the middle of the magnetised needle, so it hangs level.
- Hang the thread from a stick, a nail, or the top of a doorframe, so the needle can turn freely.
- Wait until it stops swinging and settles.
- Mark which way each end is pointing, then give it a gentle push and watch it settle again.
- Compare with a plain iron needle, hung the same way — it will not keep settling in the same direction.
A magnetic compass puts this north-south settling to direct use. Its needle is a thin magnet, balanced on a pin so it can turn freely. The needle settles pointing north-south. Turn the compass box until the dial’s own North and South line up with the needle. Every other direction is then marked as well. It is the same floating-needle compass you have just built, made more precise.
Long before the modern compass reached India, sailors used a similar idea. They floated a small magnetised iron fish in a vessel of oil. It was called a matsya-yantra. It settled the same way your needle did, and helped find directions at sea.
The device changes: a dial in a box, or a fish in oil. The idea inside both is the same one your own floating needle just showed you.
Pushing, as well as pulling
Bring two magnets’ like poles close together, and they push apart. Bring unlike poles close together, and they pull toward each other.
You do not need two magnets of your own to see this for yourself. The pages ahead show you exactly what it looks like. You can test the same rule on your own home-made compass.
Being pulled proves nothing on its own. Only being pushed away shows that both things are magnets.
In the school version: resting one magnet on round pencils so it can roll freely. Then bring a second magnet’s marked pole close to one end and watch whether it rolls toward or away.
This is what happens when the same pole comes close, and what happens when the opposite pole comes close.
Unlike poles pull toward each other; like poles push apart. A plain iron bar, tried the same way, is pulled toward either pole and never pushed away — that push is what marks a true magnet.
Instead of the school's kit: a lab compass → the floating-needle compass you built earlier; a bar magnet → a fridge magnet.
- Let the compass needle settle and come to rest.
- Bring one pole of the magnet close to the needle’s north-pointing end, without touching it.
- Watch which way the needle swings.
- Turn the magnet around and bring its other pole close to the same end, and watch again.
In the school version: two matchboxes with magnets fixed on, like poles facing each other, sped apart the moment they were brought close.
Two toy cars, each fitted with a magnet, speed apart the moment their like poles face each other. That is the same push you have just seen between two plain magnets.
The push between two like poles is strong enough to move something as light as a toy car without the two ever touching. This is the same rule as the two-magnet diagram, now shown at car scale.
A Maglev train uses this same push at railway size. Magnets with like poles face each other, one set fixed under the train and one set fixed along the track. The push lifts the train just enough to float above the rails, never touching them. With no wheels rubbing on the rail, the train loses almost none of its speed to friction.
One push moved a toy car across a tabletop. Another push holds up a whole train. The push between like poles is one rule at two sizes.
Working through wood, glass and water
Put a sheet of wood, cardboard, plastic, or glass in a magnet’s way. Its pull does not stop at the edge of that sheet. Hold a magnet on one side of any of these, and a steel object on the other. The pull still reaches across, with almost no change you can feel.
Wood, cardboard, plastic, glass and water do not block a magnet. A sheet that stops light does not stop a pull.
Instead of the school's kit: wood, cardboard, plastic and glass sheets → a wood ruler, cereal-box cardboard, a plastic ruler or bag, and a glass tumbler wall.
- Repeat the compass-deflection test from before, letting the needle settle first.
- Hold the wood between the magnet and the compass needle, then bring the magnet close again.
- Watch whether the needle still swings the same way.
- Swap the wood for cardboard, then plastic, then glass, repeating each time.
Careful: handle a cut cardboard edge, or a glass tumbler wall, carefully — both can have a sharp edge.
Instead of the school's kit: a steel ball → a large steel washer, a nut, a salvaged bearing, or a bent nail.
- Draw a winding maze path on the cardboard with a pencil.
- Place the steel object at the maze’s start, on top of the cardboard.
- Slide the magnet underneath the cardboard, following the maze path.
- Guide the steel object all the way to the maze’s end, without lifting the cardboard.
Instead of the school's kit: a paperclip → any small steel object, a pin or a small nail.
- Drop the steel object into the bowl of water.
- Hold the magnet against the outside of the bowl, or just above the water’s surface, close to the object.
- Move the magnet slowly toward the side or the top of the bowl.
- Lift the object out without wetting the magnet or your fingers.
Two things people get wrong about magnets
Here is a mistake that feels reasonable. If a magnet pulls an iron object toward itself, surely the object must be a magnet too?
It is not. Plain iron is a magnetic material, so a magnet pulls it toward either one of its poles. But the iron never pushes a pole away. Only a true magnet does both things: it is pulled toward an unlike pole, and it pushes away a like pole. That push, not the pull, is the test that actually tells a magnet apart from an ordinary piece of iron.
Attraction alone proves nothing. Only repulsion proves you are holding a real magnet.
Another mistake looks just as reasonable. Cut a magnet in half, and surely one half keeps the North end while the other keeps the South end?
That never happens, however many times you break it. Every new piece grows its own North pole and South pole again, right down to the smallest sliver anyone has ever tested. Nobody has ever found a magnet with only one pole, of any size.
Break a magnet as many times as you like — every piece still comes with both a North and a South pole.
One chapter, in short
Every idea in this chapter comes back to one property. A magnet always has two poles, North and South, and they never separate.
Left free to turn, a magnet settles pointing north to south — the idea a compass is built from. Bring an unlike pole close and two magnets pull together. Bring a like pole close and they push apart. That push, not the pull, is what tells a true magnet from a plain piece of iron. The same pull reaches through wood, cardboard, plastic, glass and water without weakening. And the very same push that moves a toy car across a table also lifts a real train off its track.
One magnet, two poles, three magnetic materials — and a push that reaches through almost anything.
Practice
Before you move on, check that three facts from this chapter are fixed in your memory. Every magnet has two poles that never separate. Iron, nickel and cobalt are magnetic materials. Like poles repel, and unlike poles attract.
If any of the three does not come back to you unprompted, read that part of the chapter again before going on.
- practice Name the two poles every magnet has.
- practice Name three materials that a magnet attracts.
- practice What happens when you bring two magnets’ like poles close together? What happens with unlike poles?
- practice True or false: breaking a magnet in half gives you one piece with only a North pole.
Answers
- North pole and South pole.
- Iron, nickel and cobalt (or a combination of these metals).
- Like poles push apart; unlike poles pull together.
- False — each new piece still has both a North pole and a South pole.
- practice Which one of these statements about magnets is false?
Answers
- C — the chapter’s rule is the opposite: like poles repel, and unlike poles attract.
You now know two separate tests. Does an object get pulled toward a magnet at all? And does it ever push a pole away? Put both tests together on an object nobody has told you the answer for.
Attraction narrows it down. Only repulsion decides it.
- Choose an object from around the house that you are not sure about.
- Test attraction first — hold it near the known magnet and see if it is pulled toward it at all.
- Test repulsion next, only if it attracted. Bring it near both poles of the known magnet, one at a time, and check whether either pole pushes it away.
- Decide what the object is, using both results. Pulled by both poles and pushed by neither means it is a magnetic material, not a magnet. Pulled by one pole and pushed away by the other means it is a true magnet.
- practice A steel spoon is pulled toward both ends of a magnet, and never pushes either end away. Is the spoon a magnet?
- practice An unlabelled bar is pulled toward one end of a known magnet, and pushes away the other end. Is the bar a magnet?
- practice Your friend says, ‘the spoon got pulled in, so it must be a magnet.’ What is wrong with this reasoning?
Answers
- No — it is a magnetic material (plain iron, most likely), not a magnet, because it never repels either pole.
- Yes — pushing one pole away while being pulled by the other is exactly what a true magnet does.
- Attraction alone never proves something is a magnet — plain iron is pulled toward either pole too. Only a repulsion test can prove it.
- practice You do the mystery-object test on a loose iron bolt from a bullock cart. It is pulled toward both ends of a known magnet, and never pushes either end away. Is the bolt a magnet?
- practice You test a rusty iron rod from a hand pump handle with a magnet. Which single result would prove it is a magnet, and not just a magnetic material?
Answers
- No — it is a magnetic material, most likely plain iron, because it is pulled toward both poles and never repels either one. Only a repulsion test proves something is a magnet.
- C — it pushes away one end of the magnet, because pushing a pole away is what plain iron never does. Only a true magnet shows that.
You have tested whether a magnet’s pull passes through wood, cardboard, plastic and glass. Try a material this chapter never printed, and see if the same rule holds.
If a material has no iron, nickel or cobalt in it, the pull goes straight through.
- practice Pick a material this chapter has not tested — cloth, paper, or a thin metal sheet. Predict: will a magnet’s pull still reach a steel pin through it?
- practice Test your prediction the same way you tested wood and cardboard. Did the pull pass through?
- practice A thin sheet of iron is placed between a magnet and a steel pin. Before you predict anything about the pin: how is this sheet different from the wood, cardboard, plastic and glass you have already tested? (Hint: is iron itself magnetic?)
Answers
- Cloth and paper should let the pull through, the same as wood and cardboard did — none of these are magnetic materials themselves.
- Answers will vary with the material tested, but cloth and paper should show almost no change, matching the pattern from wood, cardboard, plastic and glass.
- Iron is a magnetic material, and none of the others are. The magnet pulls on the iron sheet itself — hold one near a magnet and you can feel it happen. A magnet does not pull on wood, cardboard, plastic or glass at all, which is why its pull reaches the pin straight through them. That difference is what this chapter can tell you for certain. What the iron sheet then does to the pull reaching the pin behind it is a further question this chapter has not tested. Test it yourself rather than guess.
- practice Hold a magnet against the outside of a clay pot, with a steel pin resting against the inside wall near it. Does the magnet’s pull reach the pin through the clay?
- practice A jute sack is placed between a magnet and a steel nail, and the nail is still pulled toward the magnet just as strongly. What does this tell you about jute?
Answers
- Yes — clay is non-magnetic, like wood, cardboard, plastic, and glass, so the pull reaches through with no noticeable change.
- B — jute is non-magnetic, like cloth and paper, because the pull passes through it with no change.
Sometimes you are not shown a magnet’s poles directly. You are shown only how it behaves next to another magnet, or which way a compass needle points nearby. Work out the poles from that behaviour.
Work from what the magnet does, not from what it looks like — a pole has no colour of its own.
- practice Two magnets are placed end to end and they push apart. If the left magnet’s right end is a North pole, what pole is the right magnet’s left end?
- practice A compass needle’s North end swings toward one end of a nearby magnet. What pole is that end of the magnet?
- practice Two bar magnets are placed end to end and they pull together. If the left magnet’s right end is a South pole, what pole is the right magnet’s left end?
Answers
- North (like poles repel, so the two facing ends must match).
- South (unlike poles attract; the needle’s North end is pulled toward a South pole).
- North (unlike poles attract, so a South end pulls toward a North end).
- practice Two bar magnets are placed end to end, close together. The left magnet’s right end is marked North. When the two magnets are brought together, they pull toward each other instead of pushing apart. What pole is the right magnet’s left end?
- practice A compass needle is placed near one end of a magnet. The needle’s South end swings toward that end of the magnet. What pole is that end of the magnet?
Answers
- South — unlike poles pull together, and since the left magnet’s facing end is North, the right magnet’s facing end must be South.
- North — unlike poles attract, and the needle’s South end is pulled toward it, so that end of the magnet must be North.
Both traps in this chapter sound reasonable until you check them against a test. Catch them here, hidden inside short scenes.
Ask what test was actually run. Both traps survive only where nobody ran one.
- practice A friend picks up a steel nail with a magnet and claims the nail must be a magnet too, since it got pulled in. Is your friend right? Why or why not?
- practice Someone breaks a bar magnet exactly in half, expecting one piece to be only North and the other only South. What will they actually find?
- practice A shopkeeper shows you an iron rod that sticks to a magnet. He calls it ‘a strong magnet.’ What test would prove him right or wrong?
Answers
- No — plain iron is always pulled toward a magnet’s pole; it never repels one. Only a repulsion test proves something is a magnet.
- Both new pieces will have their own North pole and South pole — breaking a magnet never gives a single-pole piece.
- Bring the rod near both poles of a known magnet. If it only ever attracts and never repels either pole, it is a magnetic material, not a magnet.
- practice An iron latch on a cattle-shed gate jumps straight to a magnet the moment it comes near. A neighbour says, ‘the latch jumped, so the latch itself must be a magnet.’ Is the neighbour right?
- practice A magnet is snapped into three pieces. Someone claims that only the two outer pieces are proper magnets, since the middle piece has no free end. What is actually true of the middle piece?
Answers
- No — plain iron is always pulled toward a magnet’s pole; it never repels one. Only a repulsion test, not attraction, proves something is a magnet.
- D — it has its own North pole and South pole, like the other two. Breaking a magnet never gives a piece with only one pole.