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The smallest charge that can exist freely in nature is
A$+1\,\text{C}$
B$e = 1.6\times 10^{-19}\,\text{C}$
Cthe mass of an electron
Dzero
Answer & Solution
Correct answer: B. $e = 1.6\times 10^{-19}\,\text{C}$
1. NCERT §1.4 states the QUANTISATION of electric charge: $q = ne$ for some integer $n$.
2. The elementary charge is $e = 1.6\times 10^{-19}\,\text{C}$ — the magnitude of the charge on an electron (or a proton).
3. Free quarks would carry fractional charge, but they are confined inside hadrons and never observed in isolation. So $e$ is the smallest FREE charge.
4. Macroscopic charges always come as integer multiples of $e$.
5. Option A is a huge macroscopic charge. Option C is a MASS, not a charge. Option D contradicts the existence of charged objects.
_Source: NCERT Class 12 Physics Part 1, Ch 1 "Electric Charges and Fields", §1.4 (Quantisation of Charge) + §1.5, p. 4–5._
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