9. An assembly plant uses a hoist to raise and maneuver large objects. The hoist shown in Figure is a winch attached to a beam that can move along a track. Determine the natural frequency of the system when the hoist is used to raise a 800-kg machine part at a cable length of 9 m. Beam Cable m Beam: 3.1 m E=200 × 109 N/m² I 3.5 x 104 m4 Cable: E 200 × 109 N/m² r = 10 cm L = 9 m (a) لتش (b)