A cage of mass 2500 kg is raised and lowered by a winding drum of 1.5 m diameter. A brake dru is attached to the winding drum and the combined mass of the drums is 1000 kg and their radius. gyration is 1.2 m. The maximum speed of descent is 6 m/s and when descending at this speed, brake must be capable of stopping the load in 6 m. Find 1. the tension of the rope during stoppi at the above rate, 2. the friction torque necessary at the brake, neglecting the inertia of the rope, a 3. In a descent of 30 m, the load starts from rest and falls freely until its speed is 6 m/s. The bra is then applied and the speed is kept constant at 6 m/s until the load is 10 m from the bottom. T brake is then tightened so as to give uniform retardation, and the load is brought to rest at t bottom. Find the total time of descent. [Ans. 32 kN; 29.78 kN-m : 7.27

A cage of mass 2500 kg is raised and lowered by a winding drum of 1.5 m diameter. A brake dru is attached to the winding drum and the combined mass of the drums is 1000 kg and their radius. gyration is 1.2 m. The maximum speed of descent is 6 m/s and when descending at this speed, brake must be capable of stopping the load in 6 m. Find 1. the tension of the rope during stoppi at the above rate, 2. the friction torque necessary at the brake, neglecting the inertia of the rope, a 3. In a descent of 30 m, the load starts from rest and falls freely until its speed is 6 m/s. The bra is then applied and the speed is kept constant at 6 m/s until the load is 10 m from the bottom. T brake is then tightened so as to give uniform retardation, and the load is brought to rest at t bottom. Find the total time of descent. [Ans. 32 kN; 29.78 kN-m : 7.27

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 7.60P: The force P applied to the brake handle enables the band brake to reduce the angular speed of a...

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