How to distinguish the north and south poles?

In daily life, magnets are widely used. Then how to distinguish the north and south polarity of the magnet? Here are a few common ways to tell the difference:

Method 1: With a compass

Place a compass near a magnet, one end of the compass will attract towards the magnet's south pole, and the other end will point towards the north pole.

Method 2: Use a small magnet

Hang a small magnet on a thread or place it on a table, and then bring the magnet that needs to distinguish the north and south poles close to it, the south pole of the magnet will be attracted to the north pole of the small magnet, and the north pole of the magnet will be are attracted to the south pole of the small magnet.

Method 3: Water

Put the magnet that needs to distinguish the north and south poles in a glass of water, move the magnet slowly, when the south pole of the magnet is close to the north end of the water, the water will be "sucked" to the south end of the magnet, and when the north pole of the magnet is close to the north end of the water, water will not be attracted.

Method 4: Use iron wire

Put the iron wire on the magnet, if the two ends of the iron wire are attracted to one end of the magnet, then this end is the south pole of the magnet, otherwise it is the north pole.

It should be noted that when placing the magnet in various test tools for testing, the results should be verified several times to ensure accuracy.