Question

The transfer of integral number of ________ is one of the evidence of quantisation of electric charge. Fill in the blank with the correct answer from the options given below.

• A. photons
• B. nuclei
• C. electrons
• D. neutron

Hint:

The value of the elementary charge ($e$) is approximately $1.6 \times 10^{-19}$ Coulombs. This was famously proven by Robert Millikan in his oil-drop experiment.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Quantization of charge means that the total charge ($Q$) on a body is always an integral multiple of the smallest unit of free charge, which is the charge of an electron ($e$).

Step 2: Detailed Explanation:
When an object becomes charged, it happens because it either gains or loses a specific number of particles. These particles are electrons.
• You cannot transfer half an electron or a fraction of it.
• Therefore, the charge must be $Q = ne$, where $n$ is an integer ($\pm 1, \pm 2, \dots$).

Step 3: Final Answer:
The transfer of an integral number of electrons is evidence of the quantization of charge.