alleryStart learning →Two charges repel each other with a force of 2.0 N. If the distance between them is tripled while the charges stay the same, what is the new force between them?
A2.0 N
B18 N
C0.22 N
D0.67 N
Answer & Solution
Correct answer: C. 0.22 N
1. Coulomb's law makes force inversely proportional to the square of the distance.
2. Tripling the distance divides the force by 3 squared, which is 9.
3. F_new = 2.0 N / 9 = 0.222 N, which rounds to 0.22 N.
4. Option B multiplies by 9 instead of dividing, mistaking a bigger separation for a bigger force, which is the classic inverse-square trap.
_Source: OpenStax Physics (CC BY 4.0), Ch 18 "Static Electricity", section 18.2 Coulomb's law_
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