# Plane Kinematics of Rigid Bodies by avl14509

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```									Chapter 5
Plane Kinematics of
Rigid Bodies

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5. Plane Kinematics
Introduction
5.1 Rotation
5.2 Absolute Motion
5.3 Relative Velocity
5.4 Relative Acceleration

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5. Plane Kinematics
1.1 Introduction

Particle                                  Rigid Body

Size       Small & Not important Big & Important

Motion     Translation only                          Translation and
Rotation
Rigid body
= a body with negligible deformation
= distance between any two points in a rigid
body is constant
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5. Plane Kinematics
1.2 Motions of a Rigid Body

1. In space = three dimensions
2. In plane = two dimensions
Translation
Rectilinear
Curvilinear
Rotation

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5. Plane Kinematics
1.3 Plane Motions of a Rigid Body
Translation

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5. Plane Kinematics
1.3 Plane Motions of a Rigid Body
Rotation

General Plane Motion = Translation + Rotation

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5. Plane Kinematics
1.3 Plane Motions of a Rigid Body

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5-1 Rotation

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5-1 Rotation

ω as well as α is the same for every point
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5-1 Rotation

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5-1 Rotation
1. Rotation about a Fixed Axis
Any point in the body moves in
circular motion
For Point A

Note: v and a of other points are
different because of different r
(ω and α are the same)
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5-1 Rotation
1. Rotation about a Fixed Axis
Velocity
The equations can be rewritten
in a vector form (for plane
motion)
Direction of ω is given using the
right-hand rule.

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5-1 Rotation
1. Rotation about a Fixed Axis
Acceleration
Direction of α is given using the
right-hand rule.

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5-1 Rotation
Example 1: L-shaped bar

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5-1 Rotation
Example 2:
Starting from rest when s = 0, pulley A is given a
constant angular acceleration of 6 rad/s2. Determine
the speed of block B when it has risen 6 m.

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