Q87. two uniformly charged insulating solid spheres charges +q and -q, respectively. the spheres are placed touching each other as shown a and b , both of radiu

Q87. Two uniformly charged insulating solid spheres charges +Q and -Q, respectively. The spheres are placed touching each other as shown A and B , both of radius a, carry total in the figure. If the potential at the centre of the sphere A is V and that at the centre of B is V, then the difference V-V, is - (a)- (b) - (c) (d) 47T6,a 2T6,a 27te,a 4T&%