The attractive electrostatic force between the point charges +8.46 ✕ 10-6 and q has a magnitude of 0.967 n when the separation between the charges is 0.52 m. find the sign and magnitude of the charge q. c

The electrostatic force between two charges is given by

where
is the Coulomb's constant
is one of the charges
q is the other charge
r=0.52 m is the distance between the two charges

We know the intensity of the force between the two charges, F=0.967 N, so we can re-arrange the formula to find the value of the charge q:


And the sign of the charge is positive, because Q is positive and F is positive as well.