There was always lightning in the sky, but there was no sound, and the weather forecast didn't say it would rain. What happened? It keeps flashing.

At this time, lightning does thunder in the distance, but because the distance is too far, thunder can not be heard, and lightning can spread far through the reflection of clouds, which is commonly known as the "hotline."

Generation process

If we apply a high voltage between two electrodes, they will be closer together. When two electrodes are close to a certain distance, there will be an electric spark between them, which is called "arc discharge".

The lightning generated by thunderstorm clouds is very similar to the arc discharge mentioned above, except that lightning is fleeting, but the spark between electrodes can exist for a long time. Because the high voltage between the two electrodes can be artificially maintained for a long time, it is difficult to replenish the charge in the thunderstorm cloud immediately after discharge.

When the accumulated charge reaches a certain amount, a strong electric field is formed between different parts of the cloud or between the cloud and the ground. The average electric field intensity can reach several thousand volts/cm, and it can be as high as 10000 volts/cm in some areas.

Such a strong electric field is enough to break through the atmosphere inside and outside the cloud, so dazzling flashes are excited between the cloud and the ground or between different parts of the cloud and between different clouds. This is what people often say about lightning.

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