Type
Solution Manual
Book Title
Statics and Mechanics of Materials 2nd Edition
ISBN 13
978-0073398167

### 978-0073398167 Chapter 8 Solution Manual Part 2

February 21, 2020
PROBLEM 8.11
A couple M of magnitude 1500 N m is applied to the crank of an engine. For the
position shown, determine (a) the force P required to hold the engine system in
equilibrium, (b) the average normal stress in the connecting rod BC, which has a
450-mm2 uniform cross section.
PROBLEM 8.12
Two hydraulic cylinders are used to control the position
of the robotic arm ABC. Knowing that the control rods
attached at A and D each have a 20-mm diameter and
happen to be parallel in the position shown, determine the
average normal stress in (a) member AE, (b) member DG.
PROBLEM 8.13
The wooden members A and B are to be joined by plywood splice
plates which will be fully glued on the surfaces in contact. As part of
the design of the joint, and knowing that the clearance between the
ends of the members is to be 8 mm, determine the smallest allowable
length L if the average shearing stress in the glue is not to exceed 800
kPa.
PROBLEM 8.14
Determine the diameter of the largest circular hole that can be punched into a sheet of polystyrene 6 mm
thick, knowing that the force exerted by the punch is 45 kN and that a 55-MPa average shearing stress is
required to cause the material to fail.
PROBLEM 1.15
Two wooden planks, each
1
2
in.
thick and
9 in.
wide, are joined by the dry mortise joint shown.
Knowing that the wood used shears off along its
grain when the average shearing stress reaches
1.20 ksi, determine the magnitude P of the axial
load that will cause the joint to fail.
PROBLEM 8.16
A load P is applied to a steel rod supported as shown by an
aluminum plate into which a 0.6-in.-diameter hole has been
drilled. Knowing that the shearing stress must not exceed
18 ksi in the steel rod and 10 ksi in the aluminum plate,
determine the largest load P that can be applied to the rod.
PROBLEM 8.17
An axial load P is supported by a short
W8 40×
column of cross-
sectional area
2
11.7 in=A
and is distributed to a concrete foundation
by a square plate as shown. Knowing that the average normal stress in
the column must not exceed 30 ksi and that the bearing stress on the
concrete foundation must not exceed 3.0 ksi, determine the side a of
the plate that will provide the most economical and safe design.
PROBLEM 8.18
The axial force in the column supporting the timber beam shown is
P
20=
kips. Determine the smallest allowable length L of the bearing
plate if the bearing stress in the timber is not to exceed 400 psi.
PROBLEM 8.19
Three wooden planks are fastened together by a series of bolts to form
a column. The diameter of each bolt is 12 mm and the inner diameter
of each washer is 16 mm, which is slightly larger than the diameter of
the holes in the planks. Determine the smallest allowable outer
diameter d of the washers, knowing that the average normal stress in
the bolts is 36 MPa and that the bearing stress between the washers
and the planks must not exceed 8.5 MPa.
PROBLEM 8.20
Link AB, of width b = 50 mm and thickness t = 6 mm, is used to support
the end of a horizontal beam. Knowing that the average normal stress in
the link is 140 MPa, and that the average shearing stress in each of the
two pins is 80 MPa, determine (a) the diameter d of the pins, (b) the
average bearing stress in the link.