Direct harm of magnet to human body: Although the magnetic field of magnet has no harm to human body, direct contact with magnet itself may have the following direct harm to human body:
1, the direct attraction of magnets may cause pinch injury, especially NdFeB strong magnets and large magnets, which are more harmful to human body.
2, the magnet from the mouth into the body is more serious, and it may hurt life. Because the magnet itself is magnetic, mutual attraction in the body will cause intestinal perforation in the body, which will cause massive bleeding and endanger life. Please be careful to play with magnets directly for children.
Extended data:
1 and 1822, French physicists arago and Wojciech Luczak found that when current passes through a winding with iron blocks, the iron blocks in the winding can be magnetized.
2. 1829, American electrician Henry made some innovations to the sturgeon electromagnet device. The insulated conductor replaced the bare copper conductor, so there was no need to worry about being short-circuited by the copper conductor. Because of the insulating layer, the wires can be tightly wound together. The denser the coils, the stronger the magnetic field, which greatly improves the ability of converting electric energy into magnetic energy.
3. 183 1 year, Henry trial-produced a newer electromagnet. Although it is small in size, it can absorb 1 ton of iron. The invention of electromagnet also greatly improved the power of generator.
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