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A charge of −12 nC is given to a body. The number of excess electrons on the body is:
A7.5 × 10¹⁰
B1.92 × 10⁻²⁷
C7.5 × 10¹⁹
D1.92 × 10¹⁰
Answer & Solution
Correct answer: A. 7.5 × 10¹⁰
n = |q|/e = (12 × 10⁻⁹) / (1.6 × 10⁻¹⁹) = **7.5 × 10¹⁰ electrons**. Body is negatively charged → excess electrons (matches the −12 nC sign).
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