The Sure Test
Magnets: poles, repulsion and the invisible field
What this lesson covers
Why it matters
A magnet will happily attract a plain iron bar — AND another magnet. But there's one thing only a true magnet can do to another: push it away.
Predict first
The SURE test that a bar is a magnet is…
Plain iron is always attracted. Repulsion needs two magnets showing like poles — so repulsion, not attraction, is the fingerprint.
- repulsion — only two like poles can repel — correct
- attraction
- its weight
What you do
Walk the compass around the bar magnet and reveal its invisible territory — then declare which way the field flows.
Check yourself
Like poles ______, unlike poles ______.
N-N and S-S push apart; N-S snap together — the first law of magnets.
A freely hanging magnet always comes to rest pointing…
The Earth itself is a giant magnet — every compass is answering it.
Cutting a magnet in half gives you…
Poles always come in pairs, however small you chop.
- repel, attract — correct
- attract, repel
- both attract
- north-south — correct
- east-west
- any direction
- two complete magnets, each with N and S — correct
- a separate N piece and S piece
- two dead iron bars