Two charges repel with 36 N. You move them to half the original separation. Predict the new force.

Estimate on a scale from 0 N (0) to 200 N (200).

Hints

Coulomb’s law: $F \propto 1/r^{2}$ , halving $r$ does more than double the force.
Half the distance → $(1/2)^{-2} = 4\times$ the force.

Show the answer

144 (answers within ±10 count)

Why

$36 \times 4 = 144$ N. The inverse-square law punishes proximity quadratically, the same geometry that makes gravity soar near massive bodies makes electrostatics fierce at atomic distances.

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Two charges repel with 36 N. You move them to half the original separation. Predict the new force.

Practise Electric Charge and Coulomb's Law

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