Elevators have many safety features. In the extremely unlikely event that the multiple steel cables supporting the elevator carriage break and the emergency brakes fail to stop it, there is an oil filled piston at the bottom of the elevator shaft to cushion the landing. Model this piston as an ideal spring and assume that the 5,500 kg carriage is initially descending at 10 m/s when it contacts the spring (initially in equilibrium). The spring brings the carriage to rest over 2 m. Use conservation of energy to determine the spring constant. Assume the friction in the system is 4000 N. You need to consider the change in gravitational potential energy for this question.

Elevators have many safety features. In the extremely unlikely event that the multiple steel cables supporting the elevator carriage break and the emergency brakes fail to stop it, there is an oil filled piston at the bottom of the elevator shaft to cushion the landing. Model this piston as an ideal spring and assume that the 5,500 kg carriage is initially descending at 10 m/s when it contacts the spring (initially in equilibrium). The spring brings the carriage to rest over 2 m. Use conservation of energy to determine the spring constant. Assume the friction in the system is 4000 N. You need to consider the change in gravitational potential energy for this question.

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter6: Energy Of A System

Section: Chapter Questions

Problem 19P: A light spring with spring constant 1 200 N/m is hung from an elevated support. From its lower end...

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A block of mass 0.250 kg is placed on top of a light, vertical spring of force constant 5 000 N/m and pushed downward so that the spring is compressed by 0.100 m. After the block is released from rest, it travels upward and then leaves the spring. To what maximum height above the point of release does it rise?
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