balancing既問題.

a02ymy

A,B,Cand D are four masses attached to a rotating shaft,with their centres of mass lying at radin of 100,125,200and 150mm respectively. the planes in which the masses rotate are spaced 0.6m apart and the magnitudes of A,CandD are 15,10and 8 kg respectively. Find thevalue of the mass B and the relative angular setting for the shaft to be in compete balance

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