Problem 9.5 - Bending Stress

Problem Statement

A beam has the cross-section shown where b = 2 in. and h = 2 in. If the cross-section is subjected to an internal bending moment of 10 kip-in, determine the magnitude of the bending stress at the bottom of the cross-section.

A cross section of a beam of height 2h and width 2b is shown. The top of the beam is a rectangle of width b and height h. The bottom of the beam is two triangles each of base b and height h. The height of each triangle faces outwards. — Figure 1: The cross section of a beam.

[Problem adapted from © Kurt Gramoll CC BY NC-SA 4.0]