Exploring the magnetic field
The magnetic field around a magnet is invisible. To visualize the field, and to see how the field changes when two magnets come together, we can use iron filings. These are a byproduct of milling or grinding iron products, and have an elongated shape like a grain of rice.
To show the magnetic field: Place a magnet under a sheet of paper. Trace the outline and mark the poles. Then sprinkle iron filings slowly over the paper. Tap the paper gently to allow the filings to line up with the field.
A simple bar magnet will show field lines emanating from the poles, and lines that curve over to connect the north and south poles. In general, when two magnets are placed together, lines will connect opposite poles. If two identical poles are placed near each other, the lines from each magnet curve away from the other magnet.