1. Introduction to Mechanics of Materials.pdf

Mechanics

1. Introduction to
Mechanics of Materials
Dr. Fahad Rehman Abro

2. TTP
1. Introduction to the subject, Rigid and deformable bodies.
2. Force and Force Systems
3. Laws of Forces
4. Resolution and Composition of Forces with examples
5. Moment and Couple with examples

3. TTP
6. Varignon’sPrinciple
7. Free Body Diagram
8. Equilibrium and its Conditions
9. Friction and Laws of Friction
10. Motion along Straight Line and Newton’s laws of motion

4. TTP
11. Center of Gravity
12. Examples on Center of Gravity
13. Moment of Inertia
14. Examples on Moment of Inertia
15. Concept of Stress and Strain, Hook’s Law 2 3

5. TTP
16. Elastic Constants and Poisson’s Ratio
17. Relationship Between Elastic Constants
18. Thermal Stresses
19. Stress-Strain Diagram
20. Shear and Bending Stresses

6. Definition of Mechanics
It deals with the “Response” of
“Bodies” under “Forces”

7. Questions of common observation?

8. Questions of common observation?
Why this distance is made in a Lug Wrench ?

9. The branch of applied physics dealing with motion and forces
producing motion
◦OR
Mechanics is the science which describes and predicts the
conditions of rest or motion of bodies under the action of
forces
Definition of Mechanics

10. Bodies

11. Force

12. Forces are always in pairs

13. Responses

14. Responses
Weight more than that of
designed

15. Let’s Understand the general Classification
Matter
Solids
Rigid
Bodies
Deformable
Bodies
Fluids
Liquid
Gas
Engineering Mechanics
Mechanics of Solids
Fluid Mechanics
Pneumatics

16. Exapmpleof Rigid body
10 KN 10 KN

17. EXAMPLE OF DEFORMABLE BODY
10 KN 10 KN

18. Classification
Matter
Solids
Rigid
Bodies
Deformable
Bodies
Fluids
Liquid
Gas
Engineering Mechanics
Mechanics of Solids
Fluid Mechanics
Pneumatics
Your Subject
Mechanics of Materials

19. Difference between
“Science” and “Engineering”
SCIENCE
Science is the study of the physical world.
How the things are in the nature.
The Scientists describe “What it is”
ENGINEERING
Engineering applies scientific knowledge to
design processes, structures or equipment.
The Engineers create “what never was”

20. DIVISIONS OF ENGINEERING MECHANICS
1. STATICS
It is that branch of Engineering Mechanics, which deals with the
forces and their effects, while acting upon the bodies at rest.
2. DYNAMICS
It is that branch of Engineering Mechanics, which deals with the
forces and their effects, while acting upon the bodies in motion.
-Kinematics: withoutconsideration of the causes of motion (v, a)
-Kinetics: withconsideration of the causes of motion (v, a, F, T)

21. STATICS

22. DYNAMICS

23. DYNAMICS
What is Thrust?
Thrustis the force that propels a flying machine in the direction of motion.
What is Drag?
Dragis the force that acts opposite to the direction of motion.
Thrustanddragare like opposites: they push the airplane, or any flying object, in
opposite directions.Thrustis used to make an airplane go or gain speed

24. SYSTEM OF UNITS
Systems of Fundamental Units
1.C.G.S. units →centimetre, gram, second
2.F.P.S. units →foot, pound, second
3.M.K.S. units →metre, kilogram, second
International System of Units (SI)
◦Extension of MKS units
◦07 Base Units

25. International System of Units (SI)

26. Prerequisites for This course
High School Physics →Mechanics
Calculus
Elementary Mathematics →Algebra, Trigonometry
Ability to use Scientific Calculator

27. RECOMMENDED BOOKS
1.A Textbook of Engineering Mechanics by R.S. Khurmi
2.Engineering Mechanics: Statics by R.C. Hibbeler
3.Engineering Mechanics: Dynamics by R.C. Hibbeler
4.A Textbook of Strength of Materials by R.S. Khurmi

28. THANK YOU!!