Now that we have studied about charges and its properties, let us look at lightning. We can see that lightning is also caused due to static electricity.
- During a rain, the air currents move upwards and water droplets (in the form of rain) move downwards.
- In this process, the charges also gets separated ie the positive charges accumulate near the upper layers of the clouds and the negative charges accumulate near the lower layers.
- On the ground, positive charges accumulate.
- The magnitude of these charges grow larger and larger with time and intense rainfall.
- Under such circumstances, air (which normally is a poor conductor of electricity), loses its resistance to electricity and begins to conduct.
- When the air begins to conduct, the positive charges on the ground, meets the negative charges on the cloud and streaks of light is produced. This light an electric discharge and we see and call this as Lightning.
- The process of electric discharge can occur between clouds and earth surface or even between 2 clouds because ultimately we are looking at an interaction between + and - charges.