Chapter 1
General Principles
Engineering Mechanics: Statics
Chapter Objectives
To provide an introduction to the basic quantities and
idealizations of mechanics.
To give a statement of Newtons Laws
2.7 Position Vectors
x,y,z Coordinates
- Right-handed coordinate system
- Positive z axis points upwards, measuring the
height of an object or the altitude of a point
- Points are measured relative t
2.5 Cartesian Vectors
Right-Handed Coordinate
System
A rectangular or Cartesian coordinate system is
said to be right-handed provided:
- Thumb of right hand points
in the direction of the positive
z a
2.6 Addition and Subtraction of Cartesian Vectors
Example
Given: A = Axi + Ayj + AZk
and B = Bxi + Byj + BZk
Vector Addition
Resultant R = A + B
= (Ax + Bx)i + (Ay + By )j + (AZ + BZ) k
Vector Substra
2.4 Addition of a System of Coplanar Forces
For resultant of two or more forces:
Find the components of the forces in the specified axes
Add them algebraically
Form the resultant
In this subject, w
2.8 Force Vector Directed along a Line
In 3D problems, direction of F is specified by 2
points, through which its line of action lies
F can be formulated as a Cartesian vector
F = F u = F (r/r)
Note
2.9 Dot
Product
Dot product of vectors A and B is written as AB (Read A dot B)
Define the magnitudes of A and B and the angle between their
tails
AB = AB cos
where 0 180
Referred to as scalar
produ
Chapter 2
Force Vectors
Engineering Mechanics: Statics
Chapter Objectives
Parallelogram Law
Cartesian vector form
Dot product and angle between 2 vectors
Chapter Outline
1. Scalars and Vectors
2. Vect