A cable is placed around three parallel pipes. Two of the pipes are fixed and do not rotat...

A cable is placed around three parallel pipes. Two of the pipes are fixed and do not rotate: the third pipe is slowly rotated. Knowing that the coefficients of friction are µs = 0.25 and µk = 0.20, determine the largest weight W that can be raised (a) if only pipe A is rotated counterclockwise, (b) if only pipe C is rotated clockwise.

Fig.P8.119