Question

a small charged pith ball is suspended 2 cm above a second charged pitch ball resting on an insulated surface. if the charge of the lower ball is +20statC and it has a mass of 25 g, what charge must be on the upper ball to lift the lower ball?

Answer 1

\[F= \frac{ q _{1} q _{2}}{r ^{2} } =mg=-25*1000= \frac{ (+20statC)(-XstatC)}{ 2^{2} }\]

Answer 2

I just wonder if that so then it is at equilibrium? Isn't?