You know can produce magnet magnetic field, has attracted ferromagnetic materials such as iron, nickel, cobalt and other metallic characteristics, and introduced the magnet in the school physical points north and south poles is S pole and N pole, also are learning to between the magnets and magnets, with a rejection, heteropolar attracts the principle.
Developed today magnets are widely applied to various industries.
For the use of a single magnet do not need to pay attention to the problem of the magnetic poles, but for the magnet pairs you need to note that when using the poles.
Like some jewelry industry, electronic industry, the customer needs matching products if they are not clearly marked in advance when using magnetic pole, on the production line one by one to try, it's a waste of time.
And accidentally put wrong words need to rework, waste time and materials.
How better to distinguish between N/S pole?
Magnet manufacturer can give a magnet with north and south poles?
For that matter, is can be so sure, generally we have weak magnetic surface with the method of polar, N dot color logo or extremely.
Doubt if you have magnet, welcome to hook up with a 18025298976 clock: how much is a powerful magnet next article: order magnet matters needing attention