If a magnet keeps doing work, will its magnetism be weakened or even disappear?
There are many misconceptions about magnets and how they are magnetic.
Since the magnetism of a magnet is invisible and intangible, it will be more abstract in the eyes of many people, and it is difficult to reflect it intuitively.
First of all, whether a magnet does work or not is not directly related to its own magnetism. Generally speaking, magnetism is just a channel for magnets to store and release energy. This is very similar to springs. When we compress the spring, the spring stores energy, and when we release the hand, the energy is released.
In more technical terms, the storage and release of energy by a spring is actually the storage and release of potential energy.
The following focuses on the slightly mysterious magnetism.
How does the magnetism of a magnet come about? It needs to be analyzed from the microcosm. In essence, the magnetic poles of the microscopic units (magnetic domains) inside the magnet are kept in the same direction, and the consistency of the magnetic poles forms a stable magnetic field. In theory, as long as this consistency is maintained, the magnetism will never disappear.
It can be seen that the magnetism of a magnet is inherent, an intrinsic attribute, and has nothing to do with the outside world. Of course, it will not be weakened or even disappeared due to work done. If the magnet loses its magnetism, it can only explain one point: the order of the magnetic domains and poles is broken, and there is no other reason.
After understanding these characteristics of the magnetism, and then returning to the question, you will understand that the work done by the magnet does not consume the magnetism. magnetism be weakened or even disappear
To put it bluntly, although a magnet is magnetic, it will not do work without energy input. Here we need to emphasize the concept of work again. In the absence of energy input, it will not do work externally, and magnets are no exception. It has nothing to do with whether it is magnetic or not.
For example, two magnets that repel each other must have an external force to push one of the magnets to make them approach each other in order to make them do work. The reason for doing work is that the other magnet will be pushed when it obtains the magnetic field potential energy. magnetism be weakened or even disappear
The opposite example is, if there are two magnets attracting each other, in order for the magnets to do work, there must be an external force to separate the magnets to a certain distance, obtain the magnetic field potential energy, and release it before doing work. The performance of work is that the two magnets are attracted together .
The motor, which we cannot do without in our daily life, actually uses the above-mentioned magnetic field potential energy to continuously output energy. The process of outputting energy does not consume the magnetic field, but the energy flowing through the magnetic field.