How can two magnets demonstrate magnetic force?

When two distinct objects are shown to have the same mass using a basic two-pan scale, gravity is acting with the same force on both sides of the scale. To do this, first place an unknown mass on one side of the scale, then add known masses to the other side until the scale reaches its balance point.

Consider attempting the same procedure with a magnetic force: place one magnet with its poles oriented vertically on one pan of the scale, then balance it by adding mass to the other side in proportion to the magnet's gravitational force. After that, place the second magnet under the scale, directly beneath the first one, with its poles oriented vertically, and rebalance.

The force will be attractive and you will need to add more mass to the opposite side of the scale if the two magnets are placed so that their opposite poles are facing each other. If, on the other hand, the facing poles are the same, the force is repulsive and acts against gravity; you may need to remove mass from the opposite side or even add mass to the side that has the magnet.

You can compute the force between the two magnets at this distance by observing the difference in mass before and after applying the external magnetic field.

As a practical application, the measurement may be a little more challenging. You'll need a scale with no ferromagnetic parts. The strength of a small dipole magnet changes quickly as a function of distance. If you get the magnets too close to each other, one may flip over or they may suddenly slam together. In theory, the force between two magnets can be measured much the same way one measures the gravitational force between an object and the earth.

Two magnets can demonstrate magnetic force when their poles interact. Opposite poles (north and south) attract each other, while like poles (north and north, or south and south) repel each other. This interaction is due to the alignment of magnetic domains within the magnets, which creates a magnetic field around each magnet. When two magnets are brought close together, their magnetic fields interact, resulting in either attraction or repulsion, depending on the orientation of their poles.