A ring and a disc are initially at rest, side by side, at the top of an inclined plane which makes an angle $$60^\circ$$ with the horizontal. They start to roll without slipping at the same instant of time along the shortest path. If the time difference between their reaching the ground is $$\frac{2-\sqrt{3}}{\sqrt{10}}$$ S then the height of the top of the inclined plane, in meters, is __________. Take $$g = 10 ms^{-2}$$