The voltage must build up sufficiently to overcome the air's resistance, an electrical breakdown voltage.
电压必须足够高以克服空气的阻力,即电击穿电压。
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Chapter 4: The Climactic Discharge Once the electrical tension surpasses the air's breakdown voltage, a path of ionized air, called a " step leader, " descends from the cloud.
The breakdown voltage of an insulator is the minimum voltage that causes a portion of an insulator to become electrically conductive.
The breakdown voltage of a diode is the minimum reverse voltage to make the diode conduct in reverse. Some devices (such as TRIACs) also have a forward breakdown voltage.