May 2012
Intermediate to advanced
485 pages
10h 45m
English
The maximum instantaneous extension produced by an unknown falling weight through a height of 40 mm in a vertical bar of length 3 m and cross-sectional area of 500 mm2 is 2.1 mm. Determine the instantaneous stress induced in the vertical bar and the value of unknown weight. Take E = 2 × 105 N/mm2 (Anna Univ., Nov. 2008, ME).
Solution:
Given data: h = 40 mm, l = 3 m, A = 500 mm2, δl = 2.1 mm and E = 2 × 105 N/mm2.
Equating the work done by the falling weight to the strain energy stored is
Solving
Unknown weight, P = 1,745.8 N
Find the total strain energy stored ...