(plz help-still not solved) electrostatic force lab debate For lab, we had to do the following experiment, and me and my friend are not agreeing as to whether we have correct data: We had to charge a ball, then while holding that ball, bring it to a similarly charged ball that was hanging and free to swing. The ball that was held was always placed at the same position. For five trials, we measured how far the swinging ball swung away from the fixed ball. We found the electrostatic force on the hanging ball by equating it with the force of tension from the string and the force of gravity, resulting in F=(mgd)/L, where m is the mass of the ball, d is the displacement from equilibrium, and L is the length of the string. Therefore, for greater d, the electrostatic force was greater. For each trial we also measured the distance r between the two balls. Since the fixed ball was always placed at the same position, then r was greater only when d was greater, and, since F was greater when d was greater, then F must also be greater when r is greater. My friend is saying that this contradicts the fact that F=kq(1)q(2)/r^2 ...ie, force should be greater with lower r. I am saying that in this case, since the swinging ball was free to move, it was free to react to the fixed ball in accordance with the amount of force it felt. ie, if it felt greater force, it moved further from the fixed ball (resulting in greater r and d) Who is right?