figur e shows a long massless nonconducting rod of length l and  pivoted at the center ,       balanced with a block of weight w ,  at a distance of x from its left end .at the left end and right end of the rod are attached small charged spheres with positive charges q and 2q resp..

   a distance h beneath the each sphere there is a fixead sphere with charge +Q

 

 

 

 find the dist x when the rod is horizontal and balanced