Cause And Strength:

Whenever a magnet is brought close to a piece of ferromagnetic material, the atoms in the material are lined up; therefore the metal is temporarily magnetized. This generates a magnetic force among the atoms of the ferromagnetic substance and those in the magnet.

When a magnet is near the other magnet, the force is even stronger than it is whenever the similar magnet is close to a ferromagnetic substance. Additionally, the force can be either repulsive (i.e., the magnets repel, or push away from each other) or attractive (i.e., the magnets attract, or pull toward each other) depending on the way the magnets are turned. The force acquires stronger as the magnets are brought closer and closer altogether.

Some of the magnets are so strong that no human being can pull them separately if they get "stuck" altogether, and no person can take them all the way altogether against their mutual repulsive force. This is particularly true of electromagnets. The incredible forces available are of use in industry. A very big electromagnet can be used to carry heavy pieces of scrap iron or steel from place to place. The other electromagnets can give sufficient repulsion to suspend one object above the other. This is known as the magnetic levitation.