Make Your Own Compass
Turn an ordinary sewing needle into a compass, with the help of a magnet.
- A small bowl (not a metal one)
- A small piece of cork or foam
- A sewing needle
- A bar magnet
- A compass
What To Do
- Place some water in the bowl so the cork/foam can float easily.
- Hold the needle firmly on the bench with one finger on one end.
- Take the bar magnet and stroke the needle firmly with the South pole end, all the way from the eye to the tip. Do this at least 50 times, stroking the whole length of the needle in the same direction each time.
- Push the needle through the middle of the cork/form, then float it gently in the water.
- Allow the needle to orient itself. If you place a compass next to the bowl, you will find the compass needle and the floating needle will be pointing in the same direction – North.
(To find North using a compass place it on a flat surface, then gently turn it until the ‘N’ is lying under the red needle.)
Why Is It So?
Stroking the needle (which is made mostly of iron) with the magnet turns it into a magnet. (You can test it by trying to pick up a paperclip).
The Earth can be thought of as a giant magnet, with a magnetic North Pole and a magnetic South Pole.
A compass is simply a magnet that is allowed to spin freely so that it can line itself up with the Earth’s magnetic field.