Mechanics of Materials
Beer, Johnston, Dewolf
Lecture
2
Lara Saad
1
Center of Gravity and Centroid
Center of Gravity and
Centroid
Lara Saad
2
Center of Gravity and Centroid
Objectives
Determine the location of the center of gravity
and centroid for a body

2
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'45
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2.1 A steel rod is 2.2 m long and must not stretch more than 1.2 mm whe

Mechanics of Materials
Beer, Johnston, Dewolf
Lecture
8
Lara Saad
1
Axial Loading
Axially Loaded
Members
Deformation of Axial Members
Statically indeterminate systems
Lara Saad
2
Axial Loading
Example 2.1
SOLUTION:
The rigid bar BDE is supported by two

2.27 Each of the links AB and CD is made of aluminum (E = 75 GPa) and has a cross-
PROBLEM 2'27 sectional area of 125 mm. Knowing that they support the rigid member BC,
determine the deection of point E.
SOLUTION
EB FGD Use mam Lew BC at: :4.
Free. but,
C

Mechanics of Materials
Beer, Johnston, Dewolf
Lecture
6
Lara Saad
1
Moments of Inertia
Moments of
Inertia
Product of inertia
Principle moments of inertia
Lara Saad
2
Product of Inertia
Product of Inertia
required in order to determine
the maximum and mi

Mechanics of Materials
Beer, Johnston, Dewolf
Lecture
5
Lara Saad
1
Moments of Inertia
Moments of
Inertia
Parallel axis theorem
Radius of Gyration
Composite areas
Lara Saad
2
Moments of Inertia
Parallel Axis Theorem of an
Area
Find the moment of inerti

Mechanics of Materials
Beer, Johnston, Dewolf
Lecture
4
Lara Saad
1
Moments of Inertia
Moments of
Inertia
Definition
Parallel axis theorem
Lara Saad
2
Moments of Inertia
Definition
Whenever a distributed loading acts
perpendicular to an area and its int

9.1 CiNTER OF Gnmnnr, CENTER OF MASS. .hND THE CENTHOID OF A BODY 45 3
EXAMPLE 9.1
Locate the centroid of the red hem intu the shape of a parabolic are HS
ShUW in Fig. 9-8.
SOLUTiON
Differential Element. The differential element is shown in Fig, (L8.
It i