Physicshard · Past Paper
Two charges of 1C each are placed 1m apart in vacuum. The force between them is:
A1 N
B9 x 10^9 N
C8.85 x 10^-12 N
D9 x 10^6 N
✓ Correct Answer: B — 9 x 10^9 N
Using Coulomb's law F = k*q1*q2/r^2, where k is approx 9 x 10^9 Nm^2/C^2.
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