a. Explain the meaning of the statement 'electric charge of a body is quantised'.
b. Why can one ignore quantisation of electric charge when dealing with macroscopic i.e., large scale charges?

Explanation

Charge occurs in nature as discrete entity. One packet of charge (least quantity) is called quantum charge. It is represented by ‘e.. Generally charge of electron is represented by -e. and charge of a proton is represented by .+e.. Therefore, the charge possessed by any charged body will be an integral multiple of `pme,` i.e., ne where n- 1,2,3, `therefore q= pm "ne"`
The fact that, electric charge collections are integral multiples of the fundamental electronic charge was proved experimentally by Millikan.
b. While decaling with large scale electrical phenomonen we ignore the quantization of charge because the magnitude of charge of proton and electron is so small. For continuous charge distribution charge can be accounted in terms of charge density such as linear charge density `lambda` etc. We need not go for individual charge.