Making Magnetic Fields Visible with Water and a Needle

14.12.2024

What you need:

• A bowl of water
• A small sewing needle or paperclip
• A magnet
• A small piece of styrofoam, cork, or plastic (as a "raft")

Instructions:

1. Prepare the setup: Fill the bowl with water and place it on a stable surface.
2. Magnetize the needle: Rub the needle several times in one direction with a strong magnet to magnetize it.
3. Attach the needle: Carefully stick the needle onto a small piece of styrofoam or cork so it can float on the water like a raft.
4. Observe: Place the raft with the needle in the water. You’ll notice the needle aligns itself because it reacts to the Earth's magnetic field.
5. Experiment with the magnet: Bring a magnet close to the raft and move it around. The needle will follow the magnet’s movements.

Why does this happen?
The magnetized needle is influenced by the magnetic field of the Earth or any nearby magnet. This shows how a magnetic field, although invisible, can affect objects in its range.

Bonus Tip:
If you don’t have cork or styrofoam, you can try placing the needle directly on the surface of the water. To help it float, rub the needle with a bit of dish soap first!

This experiment is simple, fun, and a great way to see how magnetic fields work in real life.