Physics · Chapter 08
🧲 Magnetism
Invisible fields that pull and push.
💡 Invisible Force Field
A magnet has two ends — a north pole and a south pole. The rule is:
• Opposite poles attract (N pulls S)
• Like poles repel (N pushes N away)
The magnet's pull spreads in invisible lines called the magnetic field. Sprinkle iron filings near a magnet and you'll see them line up along these lines.
Earth itself is a giant magnet — that's how a compass works. The needle aligns with Earth's magnetic field, pointing roughly north. 🧭
Magnetic field lines of a bar magnet — from N to S poleWikimedia Commons / CC BY-SA 3.0
MRI machine — uses powerful electromagnets to image body tissueWikimedia Commons / CC BY-SA 3.0
🎬
The Magnetic Field
AnimationField lines flow N → S outside the magnet. A compass placed anywhere lines up with them.
🧪
Attract or Repel?
ExperimentBring two magnets close. Pick their poles — what happens?
NS
↔️
SN
ResultN ↔ S — Attract!
Opposite poles always attract. Same poles always repel.