posted by rachel .
two equally charged spheres, X and Y, repel each other with a force of 8.0 x 10^-6 N when placed a certain distance apart. Another identical, but uncharged, sphere is touched to sphere Y and then moved next to sphere X. Calculate the electric force acting on sphere Y.
let the initial charges be X,Y
Final charges will be (X+Y/2)(Y/2)
net force: (3/2)(1/2)original force or new force is 3/4 of the original.