A proposal is made to use a giant spring in the bottom of an elevator shaft as a means of safely "catching" a falling elevator car. The car freefalls until it hits a spring, which is then compressed until the car stops. The car's loaded weight is 20.0 kN. The elevator will service 20 floors. Distance between floors is 4 m. The deceleration rate of the car should not exceed 10 g's as it is being stopped. (a) determine the requirements for the spring constant and the amount the spring will compress in order to catch the falling car in the worst-case scenario. (b) what do you think about this proposal? Is it practical?

A proposal is made to use a giant spring in the bottom of an elevator shaft as a means of safely "catching" a falling elevator car. The car freefalls until it hits a spring, which is then compressed until the car stops. The car's loaded weight is 20.0 kN. The elevator will service 20 floors. Distance between floors is 4 m. The deceleration rate of the car should not exceed 10 g's as it is being stopped. (a) determine the requirements for the spring constant and the amount the spring will compress in order to catch the falling car in the worst-case scenario. (b) what do you think about this proposal? Is it practical?

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 7.78P: The figure shows a steel bar being processed by a rolling mill. Given that P=80kN and r =0.016,...

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