The function of this experiment is to determine if the north end of a magnet always points to the earth’s magnetic north pole.
Things Required:
Compass
Sewing thread
Small paper clip
Cellophane tape
Ruler
Magnet
Book
Directions:
Cut a 12-inch (30 cm) piece of thread. Attach one end of the thread to the centre of the paper clip with a very small piece of tape. Tape the free end of the thread to the end of the ruler. Set the book on the edge of a table and insert the free end of the ruler between the pages of the book so that the ruler may hang over the edge of the table. Place the paper clip on the magnet. Remove the clip from the magnet and allow it to swing freely. Observe the direction towards which the end of the paper clip points. Use the compass to determine what direction that is. Move the ruler to different positions and observe the direction the paper clip points each time.
This Is What Happens:
One end of the paper clip points south and the other points north. Moving the ruler does not affect the direction that the paper clip points.
Science Behind It:
The earth behaves as if a large bar magnet were inside it causing magnetic materials to be attracted to its opposite ends. The south end of this imaginary magnet produces the earth’s north magnetic pole, and the north ends of all magnets are attracted to this pole. The north ends of magnets are really north-seeking poles. Placing the paper clip on the magnet causes the atoms inside the paper clip to line up in a north-to-south direction. One end of the paper clip will continue to point towards the earth’s magnetic north as long as the atoms inside are lined up. Moving the position of the ruler or string will not affect the direction of the free-hanging magnetized paper clip.
Note: The paper clip will remain magnetized for only a short period. You may need to put the paper clip on the magnet to realign the electrons.
