Two identical charged spheres suspended from a common point by two massless string of length

Two identical charged spheres suspended from a common point by two massless string of length $\ell$ are initially a distance $\mathrm{d}(\mathrm{d} \ll \ell)$ apart because of their mutual repulsion. The charge begins to leak from both the spheres at a constant rate. As a result the charges approach each other with a velocity v. Then as a function of distance $x$ between them :-