17.56 Show that the system of momenta for a rigid slab in plane mo- tion reduces to a single vector, and express the distance from the mass cen- ter G to the line of action of this vector in terms of the centroidal radius of gyration k of the slab, the magnitude of the velocity of G, and the angular velocity w.

3

The centroidal mass moment of inertia ofthe pulley assembly is 20 ft-lb-s2. Determine (a) the tension in the cordsupporting 161-lb block , (b)the tension supporting the 322-lb block, and (c) the angularacceleration of the pulley system .Hint: Determine first the direction ofmotion, i.e. will block A move up ordown?

A 240-lb block is suspended from an inextensible cable which is wrapped around a drum of 1.25-ft radius rigidly attached to a flywheel. The drum and flywheel have a combined centroidal moment of intertia of 10.5 lb-ft-s^2. At the instant shown, the velocity of the block is 6 ft/s directed downward. The bearing at A as a frictional moment of 60 lb-ft. What is the kinetic energy of the system after the block moved after 4ft? (in ft-lb)