I want to know that how a atom can get a positive or negative charge, at the time of lightning and also when we do rubbing.

CBSE Class 8 Answered

I want to know that how a atom can get a positive or negative charge, at the time of lightning and also when we do rubbing.

Asked by mwar3210 | 13 Jan, 2016, 06:28: PM

Expert Answer

All materials are made up of tiny particles of matter called atoms. Normally in an atom the number of electrons and protons are equal, so that the total amounts of negative and positive charge within a material remains the same. The overall net charge of the material is zero. However, when two materials are rubbed together, electrons may get transferred from one to another. Thus the total number of opposite charges within each material changes, such that each is left with a net negative or positive charge.So, rubbing does not create changes but simply separates -ve and +ve charges which already exists in the materials.

Occurrence of Lightning

The formation of clouds involves friction (rubbing) between the water particles in the atmosphere. This friction charges the particles.
The negative charge accumulates at the bottom of the cloud, and the positive charge at its top.
As the accumulation of the charge increases, the cloud will create a positive charge on the ground.
As the amount of charge increases, the cloud will create a negative charge that tends to make a path towards the ground which results in a narrow streak of electrical discharge which is called lightning.

Answered by Yashvanti Jain | 14 Jan, 2016, 12:24: PM