1. King Fahd University of Petroleum & Minerals
Mechanical Engineering
Dynamics ME 201 BY
Dr. Meyassar N. Al-Haddad
Lecture # 23

2. Course coverage Kinematics of particle in various motion. (Chapter 12)
Force and acceleration. (Chapter 13)
Work and energy relations. (Chapter 14)
Impulse and Momentum. (Chapter 15)
Kinematics of a rigid bodies. (Chapter 16)
Force and acceleration of a rigid bodies . (Chapter 17)
Work and energy relations of a rigid bodies. (Chapter 18)
Impulse and Momentum of a rigid bodies (Chapter 19)

3. Chapter 16 Planar Kinematics of a Rigid Body Objective
To classify the various types of rigid-body.
To investigate rigid-body translation and show how to analyze motion about a fixed axis.

4. Rigid-Body Motion Types of rigid body planar motion: Translation
Rotational about fixed axis
General plane motion

5. Translation
Every line segment on the body remains parallel to its original direction
during the motion

6. Rotation about fixed axis
All particles of the body move along circular paths
except those which lie on the axis of rotation

7. General plane motion
Combination of translation and rotation

8. Example Curvilinear translation General plane motion
Rectilinear translation
Rotation about a fixed axis

9. Translation Position Velocity Acceleration
All points move with same velocity and acceleration

10. Summary chapter 12
Time dependent acceleration
Constant acceleration

11. Rotation About a Fixed axis For Line
Angular Position ( q )
Defined by the angle q measured between a fixed
reference line and r
Measured in rad
Angular Displacement
Measured as dq
Vector quantity
Measured in radians or revolutions
1 rev = 2 p rad

12. Angular velocity (w )
“the time rate of change in the angular position”
Angular acceleration
“the time rate of change of the angular velocity”
a = f(q)

13. Constant Angular Acceleration

14. Comparison

15. Motion of Point P Position : Velocity
Is defined by the position vector r
The arc-length is
Velocity
“tangent to the path”

16. Acceleration “rate of change in the velocity’s magnitude”
“rate of change in the velocity’s direction”
Direction of an is always toward O

17. r1 r2 r1 r2
s , v, a

18. Example 16-1
Rest
at = 4t m/s2
w=?
q=?

19. Thank You