Uses of Electromagnets in Everyday Life
Where electromagnets are used in everyday life — from scrapyard cranes to electric bells — and why a magnet you can switch on and off is so useful.
⏱ 12 min · 🎯 4 things to master
Every day, somewhere in Singapore, a giant crane in a scrapyard picks up a car — not with a hook, not with a claw, but with a magnet. And then, when the crane needs to drop the car in exactly the right place, the operator just flicks a switch and the car falls. No lever, no mechanical release. Just off. That trick is impossible with an ordinary magnet. It only works because the crane is using an .
Parents: each section has a simulation or a predict-and-reveal activity. Let your child tap through and explain their answer out loud before revealing — saying the keyword is how it sticks. The blue dotted words are tappable definitions; the Teacher's tip boxes name the exact PSLE keywords.
By the end you'll be able to explain why an electromagnet is chosen over a permanent magnet, name six everyday uses, and say why only iron and steel are attracted. The four ideas we'll master: switching on and off, uses of electromagnets, choosing electromagnets over permanent magnets, and magnetic materials. Let's go.
Electromagnets Can Be Switched On and Off
A is always magnetic. Stick a permanent magnet to your fridge and it stays there forever on its own. Useful for some things — but a disaster if you need to let go on command.
An electromagnet is different. It is a coil of wire wrapped around an iron or steel core. When electricity flows through the wire, the core becomes magnetic. Switch the electricity off, and the magnetism disappears instantly. Electromagnets can be switched on and off.
That one ability changes everything. It means the scrapyard crane can lift a crushed car (switch on), carry it across the yard, and drop it in exactly the right bin (switch off) — all with a flick of a switch. No permanent magnet could ever do that.
Try the virtual crane below. Predict first, then experiment.
Scrapyard Crane — Switch the Electromagnet
Predict first: How does the scrapyard crane DROP the car it picked up?
Everyday Uses of Electromagnets
Because electromagnets can be switched on and off, they show up wherever we need controllable magnetism. Here are six examples the PSLE syllabus expects you to know.
Scrapyard crane. The crane uses a powerful electromagnet to lift iron and steel objects — crushed cars, metal beams, scrap pipes. Switch on to pick up, switch off to drop. No manual hook-and-release is needed.
Electric bell. When you press the doorbell button, you complete a circuit. The electromagnet inside pulls a metal arm, which strikes the bell. Then the arm loses contact with the circuit, the electromagnet switches off, and the arm springs back — hitting the bell again and again as long as you hold the button. The rapid on-off action creates the ringing sound.
Electric motor. Electromagnets inside a motor switch on and off rapidly in sequence. Each pulse pushes a rotating part (the rotor) a little further around. Thousands of switches per second make the shaft spin smoothly — powering everything from the fans in MRT stations to the compressor in your air-conditioner.
Loudspeaker. A loudspeaker has an electromagnet that changes its magnetic strength in time with the sound signal from your phone or laptop. This pushes and pulls a paper cone back and forth, which pushes and pulls the air in front of it — and that vibrating air is the sound you hear.
Maglev train. Singapore's Thomson–East Coast Line stations are served by driverless trains. On a full maglev system (used in Shanghai and in Japanese bullet-train research), powerful electromagnets both lift the train off the track and propel it forward without any wheels touching the rails. The train floats — so there is almost no friction, and it can travel very fast.
Recycling sorter. At a recycling plant, a conveyor belt carries mixed waste. A large electromagnet sits above the belt. As the waste passes underneath, the electromagnet pulls out iron and steel items and leaves behind aluminium, plastic and glass. This separates magnetic from non-magnetic materials automatically.
🤔 Predict first: At a recycling plant, a conveyor belt carries mixed waste: steel cans, aluminium cans, and plastic bottles. An electromagnet is switched on above the belt. Which item does the electromagnet pull out first?
Why Choose an Electromagnet over a Permanent Magnet?
Now that you know the uses, there is a single big idea that explains them all. Ask yourself: why not just use a strong permanent magnet for the scrapyard crane, the electric bell, or the recycling sorter?
The answer is control. A permanent magnet cannot be turned off. Once it grabs a steel car, it holds it forever — you would need to physically pry the car off. A permanent magnet cannot vibrate on and off to ring a bell. It cannot reverse its direction to spin a motor. It cannot switch itself off so a recycling sorter releases the steel cans into the right bin.
is what makes an electromagnet the right choice.
There is a second advantage: the strength can be adjusted. Use more current, get a stronger electromagnet. Use less, get a weaker one. A scrapyard crane can be tuned to lift a small piece of pipe or a whole crushed car just by changing the current. You cannot do that with a permanent magnet of fixed strength.
🤔 Predict first: A factory needs to pick up heavy steel parts with a machine arm, then release them exactly in a mould. Should the machine arm use a permanent magnet or an electromagnet? Why?
Only Magnetic Materials Are Attracted
One more idea that trips students up: an electromagnet — like any magnet — only attracts . In PSLE Science, the magnetic materials you need to know are iron and steel.
Aluminium is a metal, but it is not magnetic. Copper is a metal, but it is not magnetic. Plastic, wood, glass, rubber — none of these are magnetic. This is why a recycling sorter can separate steel cans from aluminium cans: the electromagnet grabs the steel but ignores the aluminium.
Magnetic or non-magnetic?
Predict first: Would an electromagnet attract an aluminium drinks can?
Watch out — easily mixed up
These four pairs cause the most mistakes each year. Read them now and you will not lose easy marks.
Quick recap
🎯 Mastery check
Answer all 8 — your progress is saved on this device.
A scrapyard crane uses an electromagnet to pick up a crushed car. How does the operator drop the car into the correct bin?
Why is an electromagnet used in a scrapyard crane instead of a permanent magnet?
A recycling plant uses an electromagnet above a conveyor belt to sort waste. Which item does the electromagnet attract?
Which of the following is a magnetic material?
An electric bell rings repeatedly while the button is held down. What makes the bell ring again and again?
A factory worker needs to pick up small iron parts and place them one at a time into a mould, then release them precisely. Should the tool use a permanent magnet or an electromagnet, and why?
A student increases the current flowing through an electromagnet. What happens?
Which of the following is NOT a use of an electromagnet listed in the PSLE syllabus?