An isolated system contains charges $+5\,\text{C}$ and $-5\,\text{C}$. If they are brought together, which statement is correct?
ABoth charges are destroyed, so total charge becomes zero by disappearance of charge.
BTotal charge remains zero because charge is conserved.
CTotal charge becomes $+10\,\text{C}$ due to addition of magnitudes.
DTotal charge becomes $-10\,\text{C}$ due to attraction.
Answer & Solution
Correct answer: B. Total charge remains zero because charge is conserved.
Principle: total electric charge in an isolated system remains conserved. Here the initial total charge is $+5 + (-5) = 0\,\text{C}$. Bringing the charges together may allow neutralization in effect, but it does not mean charge is destroyed; the algebraic total remains zero throughout. Option A is tempting because students often say charges 'cancel out' by vanishing, but conservation means they do not disappear. Options C and D incorrectly add charges without regard to sign.
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