How is lightning formed?

Lightning is formed by the action of electric charge.

Lightning is a strong discharge phenomenon between clouds, between clouds and the ground, or between different parts of clouds (usually in cumulonimbus clouds). Between the positive and negative charge layers of thunderstorm clouds, when the electric field intensity is large enough, lightning will be generated. Usually storm clouds (cumulonimbus clouds) will generate charges, with negative charges at the bottom and positive charges at the top, and electromagnetism will have a direct effect.

Positive and negative charges attract each other, but air is not a good conductor. Positive charges rush to tree tops, hills, tall buildings and even human bodies in an attempt to meet negatively charged clouds; The negatively charged dendritic antenna extends downward, and the farther it extends, the closer it is to the ground. Finally, the positive and negative charges finally overcome the air barrier and connect to form lightning.

Lightning expansion

Lightning is the electro-optic light produced by discharge in cumulonimbus clouds, between clouds or between clouds. Just like the growth of a tree, lightning continues to extend the passage, and the "roots" and "leaves" develop in opposite directions at the same time. This lightning tree is electrically neutral as a whole, with one end positively charged and the other negatively charged, facing the positively charged area in the cloud.

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. The average electric field intensity can reach several thousand volts/cm.