Question

when clouds build up charge

Answer 1

hello dude

The answer is " when they collisions cause a build up of electrical charge"

I hope you may like this answer

Answer 2

Charge separation occurs because of collision of particles. The surface of an ice pellet is not exactly pure H2O, it contains an excess of OH- ion (for crystal-boundary reasons that I do not understand). That's why ice is slippery.

So, if there is a mixture of sizes of ice pellets suspended in air (not unlikely, since we see hail from time to time), and (for instance) an updraft carries the lightest (smallest radius) particles UP past larger slower particles, we can confidently expect particles to collide.

The collision of a small and large particle makes a pointy spot (where the small particle is), and the surface charge in the OH- ions flows preferentially to that spot (because the negative charge repels). When that small ice particle detaches, it carries more negative charge and the large ice particle carries less.

So, a consequence of turbulent airflow and suspended water ice is net separation of charges inside a cloud. That charge separation generates the electricity we see as lightni