Bring two magnets close and something invisible pulls them together, or pushes them apart. Kids notice it at once, and so do adults. So how do magnets work, and why does a magnetic toy feel so different from one that just clicks shut? Here is magnetism for kids and grown-ups, in plain words, with sources.
The short version
- A magnet makes an invisible magnetic field. It has a north and a south pole: opposite poles attract, like poles repel.
- In iron, nickel and cobalt, the tiny magnetic effects of electrons line up inside small regions called domains. Line the domains up and the piece becomes a permanent magnet.
- The pull and push you feel in magnetic toys is this physics, and nothing more mysterious than that.
The short answer
A magnet is, in Wikipedia’s words, “a material or object that produces a magnetic field.” The field is invisible, but it is what makes a magnet pull on iron or push and pull on other magnets. NASA puts it simply: a magnet has two ends, called its north (N) and south (S) poles, and the region where its pull and push can be felt is loosely called a magnetic field.
Which poles pull, and which push?
NASA’s Goddard education page gives the rule in one sentence: the N end repels the N end of another magnet, S repels S, and N and S attract each other. Either pole can also attract iron objects such as pins and paper clips.
| What you do | What happens |
|---|---|
| Bring a north pole near a south pole | They attract. |
| Bring a north pole near a north pole (or south near south) | They repel. |
| Bring either pole near a pin or paper clip | The iron object is attracted. |
NASA’s Mars Global Surveyor kids’ page says magnetic fields, “simply put,” are the areas of influence of a magnet. It also describes a classic trick: sprinkle iron filings over a bar magnet and they form circles that show the magnetic field lines.
Why are only some things magnetic?
Wikipedia lists the elements iron, nickel and cobalt, and their alloys, as materials that can be magnetized. The reason is inside the atoms. The same article says many materials have unpaired electron spins, and when those spins align spontaneously the material is ferromagnetic.
HyperPhysics, from Georgia State University, describes it this way for ferromagnetic materials: the unpaired electron spins line up parallel with each other in a region called a domain. Inside a domain the field is strong, but the many domains are randomly oriented with respect to one another.
What is a magnetic domain?
Wikipedia defines a magnetic domain as “a region within a magnetic material in which the magnetization is in a uniform direction.” Neighbouring domains can point different ways, so in an ordinary piece of iron their fields largely cancel outside the material.
Magnetizing changes that. According to the same article, an outside magnetic field makes the domains that point with the field grow at the expense of the others. When the field is removed, the aligned domains stay, and the piece remains magnetic. That is how a piece of ferromagnetic material becomes a permanent magnet. The article adds that heating or hammering a magnet can free the domain walls and demagnetize it.
Permanent magnets and electromagnets
Wikipedia separates two kinds. A permanent magnet is made from a material that is magnetized and creates its own persistent magnetic field. An electromagnet is a coil of wire that acts as a magnet while an electric current passes through it, and it stops when the current stops. Blocks that stick together with nothing plugged in are relying on the first kind.
Why magnetic toys feel so satisfying
We could not find a study that measures why magnetic toys feel satisfying, so here we only describe what the physics lets you feel. Wikipedia notes that the strength of a magnet’s field falls off with the cube of the distance from its centre. In everyday terms, a magnet acts strongly very close up and weakly a little further away. So the pull is felt mostly as two pieces come close.
The pole rule does the rest. Two pieces that meet the right way pull into place. Turn one magnet around and the poles that met are now alike, so they push apart. You do not need a stud, a socket or a click, only the right side facing the right way.
Wikipedia also lists children’s toys among the everyday uses of magnets, and shows a construction set made of magnetic rods and metal spheres.
Magnetism for kids: what to look for while you play
- Which sides pull together, and which push apart?
- Does the push or pull get weaker as the pieces move apart?
- Does a magnet pull on every material in the room, or only some?
These are the same questions the sources above answer, and a child can test them in a minute. One honest note: Wikipedia warns that swallowed magnets can be hazardous, especially if two or more are swallowed. Read the age and small-parts notes on any magnetic toy first.
What we would pick
For building, our Pixel Magnetic Blocks are 2 cm cubes that are magnetic on every side. The page says: two blocks touch, they snap. The magnets are encapsulated inside the ABS housing, and the sets come in 100, 200 or 400 cubes with minifigures and an instruction booklet. The page notes small parts, not for children under 3.
For driving, the RC Magnetic Snake is a remote-controlled snake: you drive it with the remote, scatter the magnetic blocks and watch the tail grow with every bite. It makes sounds as it moves, has a rechargeable built-in battery with a USB cable, and the remote takes 2 AA batteries. The page gives the age as 6 and up, says it is tested to ASTM F963-23 and CPSIA, and says the magnets are sealed inside the blocks and passed the ASTM F963 magnet test. A Single Snake comes with 7 magnetic blocks and a Battle Set has 2 snakes and 14 blocks.
Sources
- Magnet, Wikipedia: the definition, the field, iron, nickel and cobalt, permanent magnets and electromagnets, field strength falling off with distance, toys among common uses, and the warning on swallowed magnets.
- Magnetic domain, Wikipedia: the definition of a domain, why unmagnetized material has little external field, how magnetizing aligns domains, and demagnetizing by heating or hammering.
- Ferromagnetism, Wikipedia: the common ferromagnetic elements and the alignment of neighbouring atoms’ magnetic moments.
- Ferromagnetism, HyperPhysics, Georgia State University: unpaired electron spins lining up in a domain, and randomly oriented domains.
- Magnetic Fields, NASA Goddard education pages: north and south poles, the rule for repelling and attracting, and magnets attracting pins and paper clips.
- Mars Global Surveyor Magnetic Field Investigation, kids’ page, NASA: magnetic fields as areas of influence of a magnet, and iron filings showing the field.
