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Engineering Mechanics :

DYNAMICS

JJ205

PN NORHAYATI BINTI AHMAD

POLITECHNIC IBRAHIM SULTAN

Faculty of Mechanical Engineering

CHAPTER 5

BASIC CONCEPTS IN DYNAMICS

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OBJECTIVES:

• Explain the importance of dynamics in

engineering

• Explain general aspects of dynamics

• Describe fundamental units and basic definitions

in dynamics

• Describe the relationship between linear and

angular velocity, linear and angular acceleration

• Use the uniform acceleration formula for the

linear and angular motion

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Introduction

• Dynamics includes:

Kinematics: study of the geometry of motion. Kinematics is used to relate displacement, velocity, acceleration, and time without reference to the cause of motion.

Kinetics: study of the relations existing between the forces acting on a body, the mass of the body, and the motion of the body. Kinetics is used to predict the motion caused by given forces or to determine the forces required to produce a given motion.

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Kinematics

Rectilinear motion

position, velocity, and

acceleration of a particle

as it moves along a

straight line.

Angular motion

position, velocity, and

acceleration

of a particle

as it moves along

a curved line in two or

three dimensions

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Rectilinear motion

Moving in a negative

direction from the origin

Moving in a positive

direction from the origin

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Angular motion

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Basic Equation/ Units in Dynamics

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