Explain how lightning takes place.

AcademicPhysicsNCERTClass 8

Lightning is an electrical discharge produced as a result of charge separation within the atmosphere. It (a spark discharge between centres of positive and negative charge) can occur within clouds, between clouds, and between clouds and the ground.

During a thunderstorm, the air currents move upwards and the water droplets move downwards, and due to their vigorous motion charges get separated in the cloud. As a result of this process, the upper region of the cloud is accumulated with the positive charge whereas the lower region is accumulated with the negative charge. As the charges get accumulated, their magnitude becomes very large, and then these charges start flowing to meet the negatively, or positively charged region of the cloud via water droplets  (acts as a conductor) in the air. Thus, this electric discharge can be seen in the form of giant lightning sparks.

For this phenomenon to occur, a sufficiently high electric potential between two regions and a high resistance medium must be present between two clouds.

Updated on 10-Oct-2022 13:29:39