1. King Fahd University of Petroleum & Minerals
Mechanical Engineering
Dynamics ME 201 BY
Dr. Meyassar N. Al-Haddad
Lecture # 36

2. Chapter 18 Kinetics of a Particle ; Work & Energy
Objectives
To develop the principle of work and energy and apply it solve problems that involve force, velocity, and displacement.
To apply the theorem of conservation of energy to solve kinetic problems

3. General
Translation
Rotation

4. Principle of Work and Energy
Translation
Rotation

5. 14.5 Conservative Forces and Potential Energy
Conservative Force: independent of the path
Example weight & spring force
The work done by the frictional force
-> depends on the path
-> non-conservative-> the work is dissipated (heat)
Potential Energy: “capacity for doing work”
Energy comes from the motion -> Kinetic energy
position-> Potential energy

6. Gravitational potential Energy :

7. Elastic potential energy :

8. Conservation of Mechanical Energy

9. Example 18-7
M=10-kg, k=800N/m w= ?

10. Example 18-8

11. Example 18-9
mD=10-kg mR=5-kg rod AB. w= ? rolls without slipping Neglect friction

12. Thank you