In the arrangement shown in figure above, a weight
A possesses mass
m, a pulley
B possesses mass
M. Also known are the moment of inertia
I of the pulley relative to its axis and the radii of the pulley
R and
2R. The mass of the threads is negligible. If the acceleration of the weight
A after the system is set free is
w=b(M+bm)g(M+9m+IR2), find the value of
b.