4. The drum of a goods hoist has a mass of 900 kg. It has an effective diameter of 1.5 m and a radius of gyration of 0.6 m. The loaded cage has a mass of 550 kg and its frictional resistance in the vertical line of travel is 270 N. A maximum acceleration of 0.9 m/s² is required. Determine: 1. The necessary driving torque on the drum, 2. The tension in the rope during acceleration, and 3. The power devel- oped at a steady speed of 3.6 m/s. [Ans. 4.64 kN-m; 6.16 kN; 22.3 kW]

4. The drum of a goods hoist has a mass of 900 kg. It has an effective diameter of 1.5 m and a radius of gyration of 0.6 m. The loaded cage has a mass of 550 kg and its frictional resistance in the vertical line of travel is 270 N. A maximum acceleration of 0.9 m/s² is required. Determine: 1. The necessary driving torque on the drum, 2. The tension in the rope during acceleration, and 3. The power devel- oped at a steady speed of 3.6 m/s. [Ans. 4.64 kN-m; 6.16 kN; 22.3 kW]

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.81P: Calculate the horizontal force P required to push the 85-lb lawn mower at constant speed. The center...

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