9.80 - In Fig. P9.80, the cylinder and pulley turn without frictron about stationary horizonzal axles that pass through their centers. A light rope is wrapped around the cylinder, passes over the pulley, and has a \( 3.00-\mathrm{kg} \) box suspended from its free end. There is no slipping between the rope and the pulley surface. The uniform cylinder has mass 5.00 kg and radius 40.0 cm . The pulley is a uniform disk with mass 2.00 kg and radius 20.0 cm . The box is released from rest and descends as the rope unwraps from the cylinder. Find the speed of the box when it has fallen 2.50 m .
Figure P9. 80