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An elaborate pulley consists of four identical balls at the ends of spokes extending out from a rotating drum (Fig. Q9.18) A box is connected to a light, thin rope wound around the rim of the drum. When it is released from rest, the box acquires a speed V after having fallen a distance d. Now the four balls are moved inward closer to the drum, and the box is again released from rest. After it has fallen a distance d, will its speed be equal to V, greater than V, or less than V? Show or explain why.
Figure Q9.18
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