Question

explain how lighting occurs

Answer 1

When the positive and negative charges grow large enough, a giant spark - lightning - occurs between the two charges within the cloud. This is like a static electricity sparks you see, but much bigger. Most lightning happens inside a cloud, but sometimes it happens between the cloud and the ground.

Answer 2

rubbing of clouds against each other causes the exchange of charge ( from positive to negative) or ( negative to positive) causes lightning...