Two identical spheres with charges `4q,-2q` kept some distance apart exert a force F on each other if they are made to touch each other and replaced at their old positions , the force between them will be

Two identical metals balls with charges +2Q and -Q are separated by some distance and exert a force F on each other . They are joined by a conducting wire , which is then removed. The force between them will now be

Two equally charged identical small balls kept some fixed disttance apart exert a repulsive force F on each other. A similar uncharged ball, after touching one of them is placed at the mid-point of line joining the two balls. Force experienced by the third ball is

Two small identical spheres having charges +10 muC and - 90muC attract each other with a force of F newton . If they are kept in contant and then separated by the same distance, the new force between them is -

If two identical spheres having charge 16 mu C and -8 mu C are kept at certain distance apart , then the force if F. They are touched and again kept at the same distance , the force becomes.

Two charges of equal magnitudes and at a distance r exert a force F on each other. If the charges are halved and distance between them is doubled, then the new force acting on each charge is

If two identical spheres having charge 16muC and -8mu C are kept at certain distance apart, then the force is F. They are touched and again kept at the same distance, the force becomes

Two identical small conducting spheres having unequal positive charges q_1 and q_2 are separated by a distance r. If they are now made to touch each other and then separated again to the same edistance, the electrostatic formce between them in this case will be