Question
A tensile test is performed on a brass specimen 3/8" in diameter using a gage length of 2" When he load Preaches a value of 4500 lb, the distance between the gage marks has increased by 0.0048*. Assume that the material is loaded within its elastic range. A load of mass 9072g is applied to a cantilever beam. A circular rod is found to have a cross sectional area of 113mm2 Two samples are tested to failure in compression. A wood sample fails at a load of 18.000 lbs. A concrete sample fails at 62.000 lbs. The wood sample is a square block measuring 1.5" x 1.5" in cross section Te concrete sample is a cylinder with a section diameter
Explanation / Answer
b) E = F*L^3/(delta*12*pi*R^4)
F = 4500
L = 2
delta = 0.0048
R = 3/16
so,
E = 1.61 lb/in^2
a) sigma = F*l/(pi*R^3)
Strain = sigma/E
Strain = 0.0027