何 抵抗率 の タングステン ワイヤー?
抵抗率 of タングステン ワイヤー は 5.3*10^-8. タングステン has a high melting point, high resistivity, good strength, and low vapor pressure. It is the best material among all pure metals for making incandescent filaments. しかし, tungsten is hard and brittle, making it difficult to process.
いつ 電流 通過 タングステン ワイヤー および is heated to a certain temperature, the resistance value of the tungsten wire increase to a certain value (一般に, the resistance value of metal wire increase as the temperature increase)。
抵抗 of this object at normal temperature should be 1370 degree -2000 degree , but when the- cross-sectional area length of the tungsten wire changes, the resistance value will change.
In 1909, Coolidge invented the tungsten filament processing technology, which played a decisive role in the production and promotion of incandescent light bulbs. Its basic principles are still used today.
