Single lightning is usually a relatively strong direct current, which is random and disorderly, and the lightning time is very short, and the instantaneous current can reach tens of thousands. At present, human beings have no equipment to bear such a strong current.
Lightning in plateau area is mainly positive lightning, and lightning in plain hilly area is mainly negative lightning. The intensity of positive flash is higher than that of negative flash, which can generally reach several times of negative flash. When the cloud discharges, the spark is lightning and the sound is thunder.
Extended data:
The researchers observed the charge in the cloud through the atmospheric electric field instrument. It usually takes only a few minutes from the beginning of charge accumulation in the cloud to the final discharge, and it takes at most one or two hours to observe the whole discharge process of a cloud.
The bigger problem is that "which cloud in the sky will lightning" is full of randomness. Researchers can't lock the clouds where lightning is about to happen in advance, and are limited by observation instruments, so they can't observe the process of rapid charge accumulation in clouds, which objectively restricts our lightning early warning and forecasting ability.
For a high-rise building with a height of more than 45 meters, whether it is safe in lightning weather depends on whether it has side impact protection: a circle of lightning receptors is installed at a certain distance from the side of the building, and the lightning current is introduced into the ground through the lightning receptors.
The difference between AC and DC is also manifested in the type of output voltage. AC outputs AC voltage, which is generally expressed by V (or U), while DC outputs DC voltage, which is generally expressed by E (or U). In different applications, AC and DC have their own advantages and disadvantages, and they will have different applications in different fields and occasions.