A (alpha) and G (gamma) are shown above. AB is some line that crosses both AC and BC, and DC crosses BA perpendiculary and is in the same direction as the gravitional camp, which by convention points downside.
The chain will fall on the side of bigger cos*mass product:
if (cos A)*(mass of chain above BC) > (cos G)*(mass of chain above AC), it will fall to the left.
if (cos A)*(mass of chain above BC) < (cos G)*(mass of chain above AC), to the right.
Or I need to revise it again =P.
P.S.: Codification: making non-latin symbols fail to renderize since the beggining.
Other P.S.: Swithced the sides after correcting it