alleryTwo point charges q₁ and q₂ separated by distance r in vacuum experience force F. If both charges are doubled AND the distance is halved, the new force is:
A4F
B8F
C16F
D2F
Answer & Solution
Correct answer: C. 16F
F ∝ q₁q₂/r².
**New:** F' ∝ (2q₁)(2q₂)/(r/2)² = 4 × 4 × F = **16F**.
Each doubling of charge contributes factor 2 (so 4 total), halving distance contributes factor 4. 4 × 4 = 16.
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