What is meant by quantisation of charge?

The correct answer is Option (4) → The charge on any body is an integral multiple of e; a fraction of e is not found on a body.

Option (1) Charge cannot be destroyed. — Incorrect. This is part of the conservation of charge. It means the total charge of an isolated system stays the same. It says nothing about the size of the steps in which charge comes.

Option (2) Charge is a property of particles only. — Incorrect. Quantisation is about the amount of charge a body can carry. Any body, large or small, can be charged.

Option (3) Charge cannot be created. — Incorrect. This is again the conservation of charge, which holds for the total charge of an isolated system.

Option (4) The charge on any body is an integral multiple of e; a fraction of e is not found on a body. — Correct. Charge comes in whole units of the basic charge e, the charge of an electron or a proton. So a body’s charge is \( q=ne \), with \( n \) an integer.

NCERT (2026-27):
Quantisation of Charge – “Experimentally it is established that all free charges are integral multiples of a basic unit of charge denoted by e. Thus charge q on a body is always given by”

    \( q=ne \)

“where n is any integer, positive or negative. … The fact that electric charge is always an integral multiple of e is termed as quantisation of charge.”