Clouds are not charged by friction in the way we typically think of it, like rubbing a balloon on your hair. While friction does play a role in cloud formation, the main process that charges clouds is called inductive charging.

Here's how it works:

1. Water droplets and ice crystals: Clouds contain water droplets and ice crystals, especially at higher altitudes.

2. Collisions: These droplets and crystals collide with each other as they move within the cloud.

3. Charge separation: During these collisions, electrons can be transferred from one particle to another. Ice crystals tend to gain electrons and become negatively charged, while water droplets tend to lose electrons and become positively charged.

4. Separation of charges: Updrafts in the cloud carry the lighter, negatively charged ice crystals to the top of the cloud, while the heavier, positively charged water droplets remain lower.

5. Electric field: This separation of charges creates a strong electric field within the cloud.

Friction can play a minor role:

While not the primary mechanism, friction can also contribute to charge separation within a cloud. When ice crystals and water droplets collide, some frictional force can also cause electrons to be transferred.

Important note:

The charging process within clouds is complex and involves various factors, including the size and type of particles, air temperature, and the intensity of updrafts.

So, while friction might play a small role, the main mechanism for charging clouds is inductive charging, which is a process of charge separation during collisions between water droplets and ice crystals.