고체역학 (Beer) — Shearing Stresses in Beams: Problem 6.12

6.9 through 6.12 For the beam and loading shown, consider section n–n and determine (a) the largest shearing stress in that section, (b) the shearing stress at point a. 6.12 Loading: A simply supported beam of length $16 \text{ in.} + 12 \text{ in.} + 16 \text{ in.} = 44 \text{ in.}$ is subjected to two 10-kip downward concentrated loads, each located 16 in. from the supports. Section $n-n$ is located 8 in. from the left support. Cross section: A hollow square with outer dimensions $4 \text{ in.} \times 4 \text{ in.}$ and a uniform wall thickness of $1/2 \text{ in.}$ Point $a$ is located at the inner upper-left corner of the section.