7. A 2000-lb elevator machine is being hoisted into place by a crane using a single, 0.5-inch diameter, steel cable. The
Posted: Fri Jul 08, 2022 5:42 am
7. A 2000-lb elevator machine is being hoisted into place by a crane using a single, 0.5-inch diameter, steel cable. The machine is moving down at 400 ft/min when the crane motor stops suddenly with 65 ft of cable left. Using an elastic modulus of 29 million psi for the cable, and modeling as a one-DOF system with no damping, a. What is the natural frequency of the suspended machine? b. What is the machine's maximum displacement as it vibrates vertically? c. Express the vibration as a harmonic function (a sine, cosine, or sum of sine and cosine function).