Can magnetic force be converted into suction? How much can I inhale?

Answer
At present, there is no formula that can be directly converted into the suction, but the main factors to consider are as follows:
Surface Gauss value: how many magnetic lines of force are there per square centimeter? The higher the magnetic force is, the stronger the single point magnetic force is. This value has a great relationship with the thickness of the magnetizing direction of the magnet. The thicker the magnet is, the higher it is, but there is no upper limit. The increase will be very small when the thickness is about 5 ~ 10 mm, and it will be saturated when it reaches a certain thickness.
Area of magnetic force: for example, if the area of a magnet is 10 mm long x 10 mm wide, and the area of an iron sheet is only 6 mm long x 6 mm wide, then the area of magnetic force can only be calculated as 6 mm long x 6 mm wide.
Permeability of adsorbed articles: when the same magnet is used, the higher the permeability of the adsorbed articles, the stronger the suction. For example, the permeability of pure iron is higher than that of 400 series stainless steel, which means that the suction of pure iron is better than that of 400 series stainless steel. However, the permeability of aluminum, wood and other materials is extremely low (close to the permeability of vacuum and air), resulting in most of the magnetism The force will pass through them, and the magnet will not be able to generate adsorption force.
Spacing distance: for example, the glass whiteboard is about 5mm apart from the glass, which will reduce the magnetic force to about 15 ~ 30%.
If you want to use a magnet to absorb weight, it is recommended to add an iron shell or U-shaped iron. Because of the magnetic effect, the magnetic force increases, which can increase the gravity absorption.
If we want the magnet to absorb the wall, the magnet should not slide down, because the force is directional. In this case, the main reason for not sliding is friction rather than simple magnetic force. To have enough friction, we need strong magnetic force to convert. According to experience, the magnetic force of a magnet usually needs several times.