LIU BUHUA
I believe that colors have “weight.” For example, a bright red bulk and a bright blue blocks are visually balanced when they are of the same size. A lemon yellow block of the same size, however, looks lighter than the formers.
 
I tried to apply the “weight” of color on hung objects, through which the “weight” and “gravitation” can be shown straightforwardly. The “force” between lifted objects manages to approach balance through continuously rotating and swaying. Above are all self-adjustment and balance of “objects”, or say, conservation of colors.