Exciting fact

Lightning is the result of a large electrical discharge. However, the exact process is still being researched, including at ISTA. The Waitukaitis research group generates miniature lightning bolts in an experimental physics laboratory to study the process of lightning discharge in detail.

Background knowledge

Friction causes a transfer of charge, leading to an excess of either positive or negative particles. Once objects are charged by friction, they can exert force, as can be observed in the experiments. Objects with different charges attract each other. Objects with the same charge repel each other.

How does the water in the air affect the electrical force? If the environment is humid, i.e., if the air contains small water droplets, the charge becomes distributed in the air. These water droplets contain tiny charged particles (ions) that are responsible for this. Consequently, an electrostatically charged object discharges in the air and no longer exerts any force on other materials.