Konesans debaz nan leman
The ancient Greeks and Chinese discovered a naturally magnetized stone in nature and called it "magnetite". The stone can magically pick up small pieces of iron and always point in the same direction when swung at will. Early navigators used this magnet as their earliest compass to identify directions at sea. After thousands of years of development, today magnets have become a powerful material in our lives. By synthesizing alloys of different materials, the same effect as magnetite can be achieved, but the magnetic force can also be improved. Man-made magnets appeared in the 18th century, but the process of making stronger magnetic materials was slow until Alnico was made in the 1920s. Subsequently, ferrite (Ferrite) was produced in the 1950s, and rare earth magnets were produced in the 1970s Rare Earth magnets include neodymium iron boron (NdFeB) and samarium cobalt (SmCo). So far, magnetic technology has developed rapidly, and strong magnetic materials have also made components more miniaturized.
Ki direksyon mayetizasyon (oryantasyon)?
Most magnetic materials can be magnetized to saturation in the same direction, which is called the "magnetization direction" (orientation direction). Magnets without orientation (also called isotropic magnets) are much weaker than oriented magnets (also called anisotropic magnets).
What is the standard industrial definition of "North and South Poles"?
The definition of "North Pole" is that after the magnet rotates at will, its north pole points to the earth's north pole. Likewise, the south pole of the magnet points to the south pole of the earth. How can I tell the north pole of a magnet without a label?
Obviously, it is impossible to tell with the eyes alone. The magnet can be approached with a compass, and a pointer pointing to the Earth's north pole will point to the magnet's south pole.
Ki jan yo okipe ak estoke leman san danje?
Toujou fè anpil prekosyon paske leman yo pral kole ansanm poukont yo epi yo ka zongle dwèt ou. Lè leman yo atire youn ak lòt, li posib tou ke leman yo tèt yo ka domaje akòz kolizyon (frape nan kwen oswa frape fant). Kenbe leman lwen atik ki fasil magnetize, tankou diskèt, kat kredi, monitè òdinatè, mont, telefòn selilè, ekipman medikal, elatriye. Yo ta dwe kenbe leman lwen pacemaker.
Pou pi gwo leman gwosè, yo ta dwe ajoute espas plastik oswa katon ant chak moso pou asire ke leman yo ka fasil separe. Leman yo ta dwe estoke nan yon sèk, anviwònman tanperati konstan otank posib.
Ki jan yo reyalize izolasyon mayetik?
Se sèlman materyèl la ki ka adsorbe nan leman an ka jwe wòl nan izole jaden an mayetik, ak pi epè materyèl la, se pi bon efè a nan izole jaden an mayetik. Ki leman ki pi fò?
Kounye a, leman pèfòmans ki pi wo yo se leman latè ra, ak nan mitan leman latè ra, NdFeB se leman ki pi fò. Men, nan tanperati ki pi wo a 200 degre Sèlsiyis, samaryom cobalt se leman ki pi fò.
