Build a compass.
How does it work?
Once the needle is magnetized it naturally wants to align with the Earth’s stronger magnetic field. This field, called the magnetosphere, is created by electrical currents that are generated by a churning molten iron core deep inside the planet. The Earth acts as if it has a bar magnet running through it with the magnet’s south pole located near the planet’s geographic north. Since opposites attract, the north pole of a magnetized needle is attracted to it.
- Straight bar magnet
- Steel needle
- A bowl
Fill the bowl with water.
Magnetize the needle by stroking it over the bar magnet about 50 times. Make sure the needle is orientated with the needle pointing to the north of the bar magnet on each stroke.
Drop the needle onto the surface of the water – from as close as you can – to let it rest on the surface tension.