A close-coiled helical spring is manufactured from 7-mm-diameter steel wire with 45 coils. The mean coil diameter is 48 mm. The spring hangs vertically and is fixed at the top. A mass of 20 kg falls through a height of 40 mm before engaging with a collar at the lower end of the spring. Calculate (a) the maximum extension of the spring; (b) the maximum stress in the wire (G = 80 GPa).

A close-coiled helical spring is manufactured from 7-mm-diameter steel wire with 45 coils. The mean coil diameter is 48 mm. The spring hangs vertically and is fixed at the top. A mass of 20 kg falls through a height of 40 mm before engaging with a collar at the lower end of the spring. Calculate (a) the maximum extension of the spring; (b) the maximum stress in the wire (G = 80 GPa).

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter2: Axially Loaded Members

Section: Chapter Questions

Problem 2.8.12P: A bungee jumper having a mass of 55 kg leaps from a bridge, braking her fall with a long elastic...

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