Omar says a steel clip hanging from a magnet is itself a magnet while it hangs there. Is Omar correct?
Hold a magnet against a steel needle for a while, then take the magnet away. The needle now picks up staples by itself. Do the same with a soft-iron nail: the moment the magnet leaves, the nail drops everything.
You have seen that a magnet magnetizes a magnetic material near it. This lesson asks what happens when the magnet leaves.
The two materials part ways. The magnetized steel needle keeps its magnetism. It is now a permanent magnet in its own right. The soft-iron nail loses its magnetism the moment the magnetizing magnet is gone.
A magnet that loses its magnetism as soon as the magnetizing cause is removed is called a temporary magnet. Soft iron makes temporary magnets. Steel keeps its magnetism and makes permanent ones.
A magnetized steel screwdriver tip sits far from any magnet. Does it keep its magnetism?
A soft-iron rod is pulled away from the magnet that magnetized it. What happens to the rod?
A steel needle has hung from a magnet for a minute. The magnet is removed. Will the needle now attract staples on its own?
Steel keeps its magnetism after the magnetizing cause is removed.
So the needle is now a permanent magnet.
Yes. The magnetized steel needle attracts staples on its own.
A soft-iron bar hangs from a magnet, holding a staple at its lower end. The magnet is lifted away. What happens to the staple?
Soft iron loses its magnetism as soon as the magnetizing cause is removed.
With the magnet gone, the bar is no longer a magnet, so nothing holds the staple.
The staple drops. The soft-iron bar has stopped being magnetic.
Hana says a soft-iron bar is magnetic only while a magnet is near it. Is Hana correct?
Jude holds a magnet against a steel strip and a soft-iron strip, then removes it. Which strip stays magnetic?
Petra wants a compass-style needle that stays magnetic for years. Which material should she magnetize?
What makes a magnetized object a temporary magnet rather than a permanent one?