Lifting cable danger. Cranes are used to lift steel beams at construction sites (Figure a). Let's look at the danger in such a lift for a beam with length L = 12.5 m, a square cross-section with edge length w=0.458 m, and density p= 7900 kg/m³. The main cable from the crane is attached to two short cables of length h = 7.00 m symmetrically attached to the beam at distance d from the midpoint (Figure b). (a) What is the tension Tmain in the main cable when the beam is lifted at constant speed? What is the tension Tshort in each short cable if d is (b) 1.60 m, (c) 4.24 m, and (d) 5.91 m? (e) As d increases, what happens to the danger of the short cables snapping?

Lifting cable danger. Cranes are used to lift steel beams at construction sites (Figure a). Let's look at the danger in such a lift for a beam with length L = 12.5 m, a square cross-section with edge length w=0.458 m, and density p= 7900 kg/m³. The main cable from the crane is attached to two short cables of length h = 7.00 m symmetrically attached to the beam at distance d from the midpoint (Figure b). (a) What is the tension Tmain in the main cable when the beam is lifted at constant speed? What is the tension Tshort in each short cable if d is (b) 1.60 m, (c) 4.24 m, and (d) 5.91 m? (e) As d increases, what happens to the danger of the short cables snapping?

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter6: Stresses In Beams (advanced Topics)

Section: Chapter Questions

Problem 6.3.5P: A simple beam that is 18 ft long supports a uniform load of intensity q. The beam is constructed of...

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