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The principle of SUPERPOSITION for electric forces states that the net force on a charge due to multiple other charges is
Athe average of the individual forces
Bthe vector sum of pairwise Coulomb forces
Calways larger than any single pairwise force
Dalways directed toward the center of mass
Answer & Solution
Correct answer: B. the vector sum of pairwise Coulomb forces
1. NCERT §1.6 (Forces between Multiple Charges): the principle of superposition asserts that electric forces are PAIRWISE INDEPENDENT.
2. For each pair, apply Coulomb's law in isolation; then take the VECTOR sum of those forces.
3. Mathematically: $\vec{F}_\text{net} = \sum_i \vec{F}_{1i}$, where $\vec{F}_{1i}$ is the force on charge 1 due to charge $i$.
4. Each pairwise interaction is unaffected by the presence of other charges — a consequence of Coulomb's law being linear.
5. Option A is wrong — we sum, not average. Option C ignores potential cancellations. Option D is unrelated.
_Source: NCERT Class 12 Physics Part 1, Ch 1, §1.6 (Forces between Multiple Charges — superposition), p. 9–10._
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