Question

The electrostatic force between two charges is 1.8 × 10^–6 N when q₁ = q₂; that is, when the charges are equal in magnitude. If the magnitude of q₁ only is now doubled, what happens to the force between them if the distance between them is not changed?

		The force would increase by a factor of 2.
		The force would increase by a factor of 4.
		There would be no change in the force as the distance between the charges did not change.
		The force would decrease by a factor of 4.
		The force would decrease by a factor of 2.

Answer 1

$F = k*\frac{q1*q2}{d^2} \\$

When q1 is doubled, with other factors remaining the same, the force would be increased by a factor of 2 as can be clearly seen from the above equation.