Z. Док Space cone G. Body cone yk Fig. 18.24 Space cone and body cone for a flattened body (I> I') in retrograde precession.

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A uniform disc having a mass of 10 kg and a radius of gyration of 175 mm is mounted on one end of a horizontal arm of 500-mm length. The other end of the arm can rotate freely in a universal bearing. The disc is given a clockwise spin of 350 rpm as seen from the disc end of the arm. Determine the angular velocity of precession.

A solid cube of side c= 120 mm is attached as shown to a cord AB of length 240 mm. The cube spins about its diagonal BC and precesses about the vertical axis AD Knowing that 0= 25° and β= 40°, determine (a) the rate of spin of the cube, (b) its rate of precession. (See hint of Prob. 18.115.)