Experiments with Magnets: Make Your Own Compass
Experiments with Magnets: Make Your Own Compass
AIM: to turn a sewing needle into a compass. MATERIALS: one thin, lightweight sewing needle, a fairly strong magnet, a piece of paper, a glass of water. METHOD: Place a very small piece of flat paper on the water in the glass. Balance the needle on it. You should be able to push the needle around and it will stay pointing the way you set it.
Then try leading the floating needle around with the magnet. This is a fun activity by itself. Lastly, remove the needle and stroke its full length with the magnet at least three times. All strokes MUST be in the SAME direction and cover the full length of the needle. Place the needle back onto the small piece of paper. You should now see that it always swivels around to point North. WHAT IS HAPPENING? The metal crystals in the compass are randomly aligned before you stroke it with the magnet. When you do this, the crystals become aligned and the aligned crystals generate a magnetic field. The chemistry of why this happens is very complex. The needle is able to move to align its magnetic field with the earth's magnetic field due to the low friction offered by the paper on the water. Return from Experiments with Magnets to More Kids' Stuff or return to the Green Planet home page for more Solar Power Facts.
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