Can a magnet pull through things?
A magnet pulls a paper clip without touching it: through cardboard, and even through the wall of a glass. It does not pull a plastic button at all.
Watch on YouTubeWatch the episode: https://www.youtube.com/watch?v=TQWW0XstW-U
You need
- A magnet (a strong fridge magnet or a toy magnet, in one big piece)
- A steel paper clip
- A plastic button
- A piece of cardboard
- A drinking glass
Ask a grown-up to help. Ask a grown-up to help. Use one big magnet, never small or loose ones: swallowed magnets are very dangerous. Keep magnets and paper clips away from small children, and keep magnets away from phones and bank cards.
Try it
- Hold the magnet close to the paper clip. Click: it jumps to the magnet.
- Try the same with the plastic button. Nothing happens.
- Put the paper clip on top of the cardboard and hold the magnet under it.
- Guess first: can the magnet pull the clip through the cardboard?
- Move the magnet under the cardboard and watch the paper clip follow it.
- Drop the paper clip into the glass. Hold the magnet against the outside and slide it up: the clip climbs the wall.
Why did it happen?
A magnet has a pull that you cannot see. The pull reaches out around the magnet and goes right through things like paper, cardboard and glass. It only pulls some things, such as iron and steel; a paper clip is made of steel. We call those things magnetic. Plastic is not magnetic, so the button stays where it is. The pull gets weaker when the magnet is further away, so thick things can stop it.
New science word: magnetic. It means something a magnet can pull, like iron or steel.
Your challenge
Put a paper clip in a glass of water. Can your magnet pull it through the water?