SlideShare a Scribd company logo
1 of 39
Download to read offline
Rajesh P V
Carmel Polytechnic college
Rajesh P V
Carmel Polytechnic college
Forces & moments
Rajesh P V
Carmel Polytechnic college, Alappuzha, Kerala,
India,
fridayends13@gmail.com
+919497336713
Ts i- 3013- contents...
SPECIFIC OUTCOME
MODULE – I
 1.1.0 Understand Moment of a force
 1.1.1 Identify the various types of forces
 1.1.2 State the principle of moments
CONTENT DETAILS
MODULE – I
 Forces and Moments
 Definition of force –types of forces, Moment of force – types
of moments – principle of moments (proof
 not required)
FORCE
 MATTER - The substance of which all the things are
composed.
 BODY - A limited quantity of matter occupying a
certain portion of the space.
 MASS - The quantity of matter contained in a body.
FORCE...
 Force is anything which changes or tends to change the
state of rest or of uniform motion along a straight line.
 Force is the action of one body on any other body.
 Force is the product of mass (m) and acceleration (a)
F = m x a
 Force is a vector quantity.
 Unit-Newton (N) , kN, kg m/s2, dyne(cgs unit), pound
force etc.
(PVC)
FORCE...
Some examples of force are:
 Gravitational force,
 Electric force,
 Magnetic force,
 Nuclear force,
 Frictional force etc.
Types of forces...
 Contact force
 Non contact force
TYPEs OF FORCEs
.CONTACT FORCES.
Force which represent the result of physical contact
between two objects that is one of the object exerts force
on the other is called contact forces.
Forces which act on a body either directly or through a
medium are called contact forces.
Eg: Stretching of a spring balance, kicking of football, etc.
Types of forces...
NON CONTACT FORCE
Forces which act through spaces without
making direct contact with the body are called
non-contact forces.
Force,moment of a force and couple
Elements ( specifications) of FORCE
 Magnitude.
 Direction.
 Point of application.
(PVC)
PRINCIPLE OF TRANSMISSIBILITY
External effect of a force is independent of its point of
application.
Or
External effect of a force on a rigid body is the same for all
points of application along its line of action.
RESOLUTION OF FORCE
 The process of splitting up the given force into a number of
components , without changing its effect on the body is
called resolution of a force.
 A force is, generally, resolved along two mutually
perpendicular directions.
Horizontal component , Fx=F cosθ
Vertical component,Fy =F sinθ
(PVC)
RESOLUTION OF FORCE
RECTANGULAR COMPONENTS
Horizontal component Fx = F cosθ
Vertical component Fy=Fsinθ
RESULTANT of forces
 Resultant- It is a single force which has the same
action or effect as a given system of forces.
RESULTANT
EQUILIBRANT
 Equilibrant- It is a single force which is equal in
magnitude but opposite in direction to the resultant of
a system of forces.
system of forces
 Parallel forces
 Non parallel forces
 Like parallel forces
 Unlike parallel forces
 Concurrent forces
 Non concurrent forces
 Collinear forces
 Non collinear forces
 Coplanar forces
 Non coplanar forces
 Coplanar concurrent forces
 Coplanar non concurrent forces
 Coplanar like parallel forces
 Coplanar unlike parallel forces
 Non coplanar concurrent forces
 Non coplanar non concurrent forces, etc.
Law of forces
 Triangle law of forces
 Parallelogram law of forces
 Polygon law of forces
Triangle law of forces
If two forces are represented both in magnitude and
direction by the adjacent sides of a triangle taken in
order, then their resultant is represented by the third
side of the triangle taken in the reverse order.
Parallelogram law of forces
If two forces are represented both in magnitude
and direction as the adjacent sides of a
parallelogram drawn from a point, then the
resultant is represented by the diagonal of the
parallelogram drawn from the same point.
polygon law of forces
If any number of forces, acting on a particle , be
represented ,in magnitude and direction by the
sides of a polygon ,taken in order, then the forces
will be in equilibrium.
Moment of a force
 Moment of a force about a given point is the turning effect
of the force about the point and is measured as the the
product of that force and the perpendicular distance
between the point and the line of action of the force.
 Moment of a force =force x the perpendicular distance
between the point and the line of action of the force.
= F x d
Unit -Newton metre (Nm) .
(PVC)
Moment of a force
TYPES OF MOMENTS
Clockwise moment
Anticlockwise moment
TYPES OF MOMENTS
CLOCKWISE MOMENT
If force acting on a body has the tendency to rotate the body in
clockwise direction the moment produced is known as
clockwise moment these are taken as negative (-)
TYPES OF MOMENTS
ANTICLOCKWISE MOMENT
If a force acting on a body has the tendency to rotate the body
in anticlockwise direction, then the moment as produced is
called anticlockwise moment its taken as positive (+)
principle of moments
(varignon’s theorem)
 The Moment of a force about any point is equal to the
algebraic sum of the moments of its components
about the same point.
Or
 The algebraic sum of the moments of a system of
unequal forces about any point in their plane is equal
to the moment of their resultant about that point.
(PVC)
couple
 Two equal and unlike parallel forces whose line of
action are different constitute a couple.
 Unit - Newton metre (Nm),kNm, kNmm, etc.
 Effect of couple is to produce turning moment or
rotation.
moment of a couple
 The product of one of the two forces forming the
couple and the arm of the couple.
 The arm of the couple is the perpendicular distance
between the lines of action of the forces.
 Unit - Newton metre (Nm), kNm, kNmm, etc
(PVC)
moment of a couple
Arm of the couple = LM
Moment of the couple = Force x Arm of the couple
= F x LM
(PVC)
Torque
Moment of the couple is called torque
Unit -Newton metre (Nm), kNm, kNmm, etc
(PVC)
Torque
MAIN CHARACTERISTICS OF COUPLE
 The algebraic sum of the forces, having the couple, is zero.
 The algebraic sum of moment of the forces, constituting
couple, about any point is the same, and equal to the moment
of couple itself.
 A couple can't be balanced by a single force, but can be
balanced only by a couple, however of opposite sense.
 Any number of coplanar couples can be reduced to single
couple, whose magnitude will be equal to algebraic sum of
moments of all the couples.
previous questions ..
 Define force
 What are the different types of forces?
 What are the system of forces?
 Define moment of a force?
 What are the different types of moments?
 Define couple?
 Define moment of a couple.
 State Varignon’s theorem ( State the principle of moments)
 What is the arm of the couple?
Additional questions ..
 Write the unit of 1.)force, 2.)moment of a force, 3.)couple
5.)moment of a couple and 6.)torque.
 State principle of transmissibility.
 What are the elements (specifications) of force?
 State the triangle law of forces.
 State the parallelogram law of forces.
 State the polygon law of forces.
 What is resolution of forces?
 Differentiate between resultant and equilibrant.
 Define couple?
 State Varignon’s theorem ( State the principle of moments)
 List the characteristics of couple?
References..
 1. R.S.Khurmi : Applied Mechanics & Strength of Materials;
S. Chand Publishing
 2. M.Chakrabroti : Strength of materials ; S.K Kataria
&sons.
 3. R.K.Rajput : Strength of Materials ; S. Chand Publishing
 4. S.S.Bhavikatti : Strength of Materials ; Vikas Publishing
House Pvt Ltd,
 5.K.N.A.G.K. Manikanta: Theory of structures –I; Radiant
Publishing House
Thank you

More Related Content

What's hot (20)

Introduction to mechanics
Introduction to mechanicsIntroduction to mechanics
Introduction to mechanics
 
Lecture 1 Introduction to statics Engineering Mechanics hibbeler 14th edition
Lecture 1 Introduction to statics Engineering Mechanics hibbeler 14th editionLecture 1 Introduction to statics Engineering Mechanics hibbeler 14th edition
Lecture 1 Introduction to statics Engineering Mechanics hibbeler 14th edition
 
Chapter 2
Chapter 2Chapter 2
Chapter 2
 
Static Force Analysis
Static Force AnalysisStatic Force Analysis
Static Force Analysis
 
System of forces
System of forcesSystem of forces
System of forces
 
Engineering Mechanics Fundamentals
Engineering Mechanics FundamentalsEngineering Mechanics Fundamentals
Engineering Mechanics Fundamentals
 
Engineering Mechanics
Engineering MechanicsEngineering Mechanics
Engineering Mechanics
 
Lami's Theorem | Mechanical Engineering
Lami's Theorem | Mechanical EngineeringLami's Theorem | Mechanical Engineering
Lami's Theorem | Mechanical Engineering
 
Moment
MomentMoment
Moment
 
Coplanar concurrent forces
Coplanar concurrent forcesCoplanar concurrent forces
Coplanar concurrent forces
 
Free body diagram
Free body diagramFree body diagram
Free body diagram
 
INTRODUCTION TO ENGINEERING MECHANICS - SPP.pptx
INTRODUCTION TO ENGINEERING MECHANICS - SPP.pptxINTRODUCTION TO ENGINEERING MECHANICS - SPP.pptx
INTRODUCTION TO ENGINEERING MECHANICS - SPP.pptx
 
Applied mechanics
Applied mechanicsApplied mechanics
Applied mechanics
 
Resultant of forces
Resultant of forcesResultant of forces
Resultant of forces
 
Torque
TorqueTorque
Torque
 
Fundamentals of statics
Fundamentals of statics Fundamentals of statics
Fundamentals of statics
 
Mechanics ppt 1
Mechanics ppt 1Mechanics ppt 1
Mechanics ppt 1
 
Dynamics
DynamicsDynamics
Dynamics
 
Dynamics ppt
Dynamics pptDynamics ppt
Dynamics ppt
 
FRICTION
FRICTIONFRICTION
FRICTION
 

Similar to Force,moment of a force and couple

Engineering Mechanics.pptx
Engineering Mechanics.pptxEngineering Mechanics.pptx
Engineering Mechanics.pptxYogesh Kulkarni
 
engineering mechanics - statics and dynamics
engineering mechanics - statics and dynamicsengineering mechanics - statics and dynamics
engineering mechanics - statics and dynamicsVelmuruganV15
 
ENGINEERING MECHANICS UNIT 1 SPPU
ENGINEERING MECHANICS UNIT 1 SPPUENGINEERING MECHANICS UNIT 1 SPPU
ENGINEERING MECHANICS UNIT 1 SPPUShripad Deshpande
 
Engineering mechanics
Engineering mechanics Engineering mechanics
Engineering mechanics Ashish Mishra
 
Lecture 4 - Resultant of Forces - Part 1.pptx
Lecture 4 - Resultant of Forces - Part 1.pptxLecture 4 - Resultant of Forces - Part 1.pptx
Lecture 4 - Resultant of Forces - Part 1.pptxMarjorieJeanAnog
 
Unit 1 ( introduction basic)
Unit 1 ( introduction basic)Unit 1 ( introduction basic)
Unit 1 ( introduction basic)V.Mohan Kumar
 
Engineering mechanics gd
Engineering mechanics gdEngineering mechanics gd
Engineering mechanics gdankit sharma
 
Force System-Engineering Mechanics
Force System-Engineering MechanicsForce System-Engineering Mechanics
Force System-Engineering MechanicsVinod Shikhare
 
L0-T1 MOS OCT 2020.pptx .
L0-T1 MOS OCT 2020.pptx                          .L0-T1 MOS OCT 2020.pptx                          .
L0-T1 MOS OCT 2020.pptx .happycocoman
 
General system of forces unit 4 bce & engg mechanics
General system of forces unit 4 bce & engg mechanicsGeneral system of forces unit 4 bce & engg mechanics
General system of forces unit 4 bce & engg mechanicsParimal Jha
 
Unit 1 statics of particles
Unit 1 statics of particlesUnit 1 statics of particles
Unit 1 statics of particlesBaluMahendran17
 
enggmechanicsbya-170923041240-converted.pptx
enggmechanicsbya-170923041240-converted.pptxenggmechanicsbya-170923041240-converted.pptx
enggmechanicsbya-170923041240-converted.pptxswathirani7
 
Diploma i em u iii concept of moment & friction
Diploma i em u   iii concept of moment & frictionDiploma i em u   iii concept of moment & friction
Diploma i em u iii concept of moment & frictionRai University
 
ME3351 ENGG. MECHANICS MLM.pdf
ME3351 ENGG. MECHANICS MLM.pdfME3351 ENGG. MECHANICS MLM.pdf
ME3351 ENGG. MECHANICS MLM.pdfSathiyaGK
 

Similar to Force,moment of a force and couple (20)

Engineering Mechanics.pptx
Engineering Mechanics.pptxEngineering Mechanics.pptx
Engineering Mechanics.pptx
 
engineering mechanics - statics and dynamics
engineering mechanics - statics and dynamicsengineering mechanics - statics and dynamics
engineering mechanics - statics and dynamics
 
ENGINEERING MECHANICS UNIT 1 SPPU
ENGINEERING MECHANICS UNIT 1 SPPUENGINEERING MECHANICS UNIT 1 SPPU
ENGINEERING MECHANICS UNIT 1 SPPU
 
Engineering mechanics
Engineering mechanics Engineering mechanics
Engineering mechanics
 
Lecture 4 - Resultant of Forces - Part 1.pptx
Lecture 4 - Resultant of Forces - Part 1.pptxLecture 4 - Resultant of Forces - Part 1.pptx
Lecture 4 - Resultant of Forces - Part 1.pptx
 
Ctm 154[1]
Ctm 154[1]Ctm 154[1]
Ctm 154[1]
 
Statics of particle
Statics of particle Statics of particle
Statics of particle
 
Unit 1 ( introduction basic)
Unit 1 ( introduction basic)Unit 1 ( introduction basic)
Unit 1 ( introduction basic)
 
Engineering mechanics gd
Engineering mechanics gdEngineering mechanics gd
Engineering mechanics gd
 
Force System-Engineering Mechanics
Force System-Engineering MechanicsForce System-Engineering Mechanics
Force System-Engineering Mechanics
 
L0-T1 MOS OCT 2020.pptx .
L0-T1 MOS OCT 2020.pptx                          .L0-T1 MOS OCT 2020.pptx                          .
L0-T1 MOS OCT 2020.pptx .
 
General system of forces unit 4 bce & engg mechanics
General system of forces unit 4 bce & engg mechanicsGeneral system of forces unit 4 bce & engg mechanics
General system of forces unit 4 bce & engg mechanics
 
Unit 1 statics of particles
Unit 1 statics of particlesUnit 1 statics of particles
Unit 1 statics of particles
 
enggmechanicsbya-170923041240-converted.pptx
enggmechanicsbya-170923041240-converted.pptxenggmechanicsbya-170923041240-converted.pptx
enggmechanicsbya-170923041240-converted.pptx
 
force.docx
force.docxforce.docx
force.docx
 
Diploma i em u iii concept of moment & friction
Diploma i em u   iii concept of moment & frictionDiploma i em u   iii concept of moment & friction
Diploma i em u iii concept of moment & friction
 
12475602.ppt
12475602.ppt12475602.ppt
12475602.ppt
 
12475602.ppt
12475602.ppt12475602.ppt
12475602.ppt
 
ME3351 ENGG. MECHANICS MLM.pdf
ME3351 ENGG. MECHANICS MLM.pdfME3351 ENGG. MECHANICS MLM.pdf
ME3351 ENGG. MECHANICS MLM.pdf
 
Applied mechanics
Applied mechanicsApplied mechanics
Applied mechanics
 

Recently uploaded

Practical Research 1 Lesson 9 Scope and delimitation.pptx
Practical Research 1 Lesson 9 Scope and delimitation.pptxPractical Research 1 Lesson 9 Scope and delimitation.pptx
Practical Research 1 Lesson 9 Scope and delimitation.pptxKatherine Villaluna
 
3.21.24 The Origins of Black Power.pptx
3.21.24  The Origins of Black Power.pptx3.21.24  The Origins of Black Power.pptx
3.21.24 The Origins of Black Power.pptxmary850239
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapitolTechU
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxDr. Asif Anas
 
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptxClinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptxraviapr7
 
The basics of sentences session 10pptx.pptx
The basics of sentences session 10pptx.pptxThe basics of sentences session 10pptx.pptx
The basics of sentences session 10pptx.pptxheathfieldcps1
 
Philosophy of Education and Educational Philosophy
Philosophy of Education  and Educational PhilosophyPhilosophy of Education  and Educational Philosophy
Philosophy of Education and Educational PhilosophyShuvankar Madhu
 
Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...raviapr7
 
Presentation on the Basics of Writing. Writing a Paragraph
Presentation on the Basics of Writing. Writing a ParagraphPresentation on the Basics of Writing. Writing a Paragraph
Presentation on the Basics of Writing. Writing a ParagraphNetziValdelomar1
 
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptxPractical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptxKatherine Villaluna
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsEugene Lysak
 
Benefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive EducationBenefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive EducationMJDuyan
 
UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024UKCGE
 
How to Use api.constrains ( ) in Odoo 17
How to Use api.constrains ( ) in Odoo 17How to Use api.constrains ( ) in Odoo 17
How to Use api.constrains ( ) in Odoo 17Celine George
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?TechSoup
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17Celine George
 
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdfMaximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdfTechSoup
 
HED Office Sohayok Exam Question Solution 2023.pdf
HED Office Sohayok Exam Question Solution 2023.pdfHED Office Sohayok Exam Question Solution 2023.pdf
HED Office Sohayok Exam Question Solution 2023.pdfMohonDas
 
Human-AI Co-Creation of Worked Examples for Programming Classes
Human-AI Co-Creation of Worked Examples for Programming ClassesHuman-AI Co-Creation of Worked Examples for Programming Classes
Human-AI Co-Creation of Worked Examples for Programming ClassesMohammad Hassany
 

Recently uploaded (20)

Practical Research 1 Lesson 9 Scope and delimitation.pptx
Practical Research 1 Lesson 9 Scope and delimitation.pptxPractical Research 1 Lesson 9 Scope and delimitation.pptx
Practical Research 1 Lesson 9 Scope and delimitation.pptx
 
3.21.24 The Origins of Black Power.pptx
3.21.24  The Origins of Black Power.pptx3.21.24  The Origins of Black Power.pptx
3.21.24 The Origins of Black Power.pptx
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptx
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptx
 
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptxClinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
 
The basics of sentences session 10pptx.pptx
The basics of sentences session 10pptx.pptxThe basics of sentences session 10pptx.pptx
The basics of sentences session 10pptx.pptx
 
Philosophy of Education and Educational Philosophy
Philosophy of Education  and Educational PhilosophyPhilosophy of Education  and Educational Philosophy
Philosophy of Education and Educational Philosophy
 
Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...
 
Presentation on the Basics of Writing. Writing a Paragraph
Presentation on the Basics of Writing. Writing a ParagraphPresentation on the Basics of Writing. Writing a Paragraph
Presentation on the Basics of Writing. Writing a Paragraph
 
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptxPractical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptx
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George Wells
 
Benefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive EducationBenefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive Education
 
UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024
 
Personal Resilience in Project Management 2 - TV Edit 1a.pdf
Personal Resilience in Project Management 2 - TV Edit 1a.pdfPersonal Resilience in Project Management 2 - TV Edit 1a.pdf
Personal Resilience in Project Management 2 - TV Edit 1a.pdf
 
How to Use api.constrains ( ) in Odoo 17
How to Use api.constrains ( ) in Odoo 17How to Use api.constrains ( ) in Odoo 17
How to Use api.constrains ( ) in Odoo 17
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17
 
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdfMaximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
 
HED Office Sohayok Exam Question Solution 2023.pdf
HED Office Sohayok Exam Question Solution 2023.pdfHED Office Sohayok Exam Question Solution 2023.pdf
HED Office Sohayok Exam Question Solution 2023.pdf
 
Human-AI Co-Creation of Worked Examples for Programming Classes
Human-AI Co-Creation of Worked Examples for Programming ClassesHuman-AI Co-Creation of Worked Examples for Programming Classes
Human-AI Co-Creation of Worked Examples for Programming Classes
 

Force,moment of a force and couple

  • 1. Rajesh P V Carmel Polytechnic college
  • 2. Rajesh P V Carmel Polytechnic college
  • 3. Forces & moments Rajesh P V Carmel Polytechnic college, Alappuzha, Kerala, India, fridayends13@gmail.com +919497336713
  • 4. Ts i- 3013- contents... SPECIFIC OUTCOME MODULE – I  1.1.0 Understand Moment of a force  1.1.1 Identify the various types of forces  1.1.2 State the principle of moments CONTENT DETAILS MODULE – I  Forces and Moments  Definition of force –types of forces, Moment of force – types of moments – principle of moments (proof  not required)
  • 5. FORCE  MATTER - The substance of which all the things are composed.  BODY - A limited quantity of matter occupying a certain portion of the space.  MASS - The quantity of matter contained in a body.
  • 6. FORCE...  Force is anything which changes or tends to change the state of rest or of uniform motion along a straight line.  Force is the action of one body on any other body.  Force is the product of mass (m) and acceleration (a) F = m x a  Force is a vector quantity.  Unit-Newton (N) , kN, kg m/s2, dyne(cgs unit), pound force etc. (PVC)
  • 7. FORCE... Some examples of force are:  Gravitational force,  Electric force,  Magnetic force,  Nuclear force,  Frictional force etc.
  • 8. Types of forces...  Contact force  Non contact force
  • 9. TYPEs OF FORCEs .CONTACT FORCES. Force which represent the result of physical contact between two objects that is one of the object exerts force on the other is called contact forces. Forces which act on a body either directly or through a medium are called contact forces. Eg: Stretching of a spring balance, kicking of football, etc.
  • 10. Types of forces... NON CONTACT FORCE Forces which act through spaces without making direct contact with the body are called non-contact forces.
  • 12. Elements ( specifications) of FORCE  Magnitude.  Direction.  Point of application. (PVC)
  • 13. PRINCIPLE OF TRANSMISSIBILITY External effect of a force is independent of its point of application. Or External effect of a force on a rigid body is the same for all points of application along its line of action.
  • 14. RESOLUTION OF FORCE  The process of splitting up the given force into a number of components , without changing its effect on the body is called resolution of a force.  A force is, generally, resolved along two mutually perpendicular directions. Horizontal component , Fx=F cosθ Vertical component,Fy =F sinθ (PVC)
  • 15. RESOLUTION OF FORCE RECTANGULAR COMPONENTS Horizontal component Fx = F cosθ Vertical component Fy=Fsinθ
  • 16. RESULTANT of forces  Resultant- It is a single force which has the same action or effect as a given system of forces.
  • 18. EQUILIBRANT  Equilibrant- It is a single force which is equal in magnitude but opposite in direction to the resultant of a system of forces.
  • 19. system of forces  Parallel forces  Non parallel forces  Like parallel forces  Unlike parallel forces  Concurrent forces  Non concurrent forces  Collinear forces  Non collinear forces  Coplanar forces  Non coplanar forces  Coplanar concurrent forces  Coplanar non concurrent forces  Coplanar like parallel forces  Coplanar unlike parallel forces  Non coplanar concurrent forces  Non coplanar non concurrent forces, etc.
  • 20. Law of forces  Triangle law of forces  Parallelogram law of forces  Polygon law of forces
  • 21. Triangle law of forces If two forces are represented both in magnitude and direction by the adjacent sides of a triangle taken in order, then their resultant is represented by the third side of the triangle taken in the reverse order.
  • 22. Parallelogram law of forces If two forces are represented both in magnitude and direction as the adjacent sides of a parallelogram drawn from a point, then the resultant is represented by the diagonal of the parallelogram drawn from the same point.
  • 23. polygon law of forces If any number of forces, acting on a particle , be represented ,in magnitude and direction by the sides of a polygon ,taken in order, then the forces will be in equilibrium.
  • 24. Moment of a force  Moment of a force about a given point is the turning effect of the force about the point and is measured as the the product of that force and the perpendicular distance between the point and the line of action of the force.  Moment of a force =force x the perpendicular distance between the point and the line of action of the force. = F x d Unit -Newton metre (Nm) . (PVC)
  • 25. Moment of a force
  • 26. TYPES OF MOMENTS Clockwise moment Anticlockwise moment
  • 27. TYPES OF MOMENTS CLOCKWISE MOMENT If force acting on a body has the tendency to rotate the body in clockwise direction the moment produced is known as clockwise moment these are taken as negative (-)
  • 28. TYPES OF MOMENTS ANTICLOCKWISE MOMENT If a force acting on a body has the tendency to rotate the body in anticlockwise direction, then the moment as produced is called anticlockwise moment its taken as positive (+)
  • 29. principle of moments (varignon’s theorem)  The Moment of a force about any point is equal to the algebraic sum of the moments of its components about the same point. Or  The algebraic sum of the moments of a system of unequal forces about any point in their plane is equal to the moment of their resultant about that point. (PVC)
  • 30. couple  Two equal and unlike parallel forces whose line of action are different constitute a couple.  Unit - Newton metre (Nm),kNm, kNmm, etc.  Effect of couple is to produce turning moment or rotation.
  • 31. moment of a couple  The product of one of the two forces forming the couple and the arm of the couple.  The arm of the couple is the perpendicular distance between the lines of action of the forces.  Unit - Newton metre (Nm), kNm, kNmm, etc (PVC)
  • 32. moment of a couple Arm of the couple = LM Moment of the couple = Force x Arm of the couple = F x LM (PVC)
  • 33. Torque Moment of the couple is called torque Unit -Newton metre (Nm), kNm, kNmm, etc (PVC)
  • 35. MAIN CHARACTERISTICS OF COUPLE  The algebraic sum of the forces, having the couple, is zero.  The algebraic sum of moment of the forces, constituting couple, about any point is the same, and equal to the moment of couple itself.  A couple can't be balanced by a single force, but can be balanced only by a couple, however of opposite sense.  Any number of coplanar couples can be reduced to single couple, whose magnitude will be equal to algebraic sum of moments of all the couples.
  • 36. previous questions ..  Define force  What are the different types of forces?  What are the system of forces?  Define moment of a force?  What are the different types of moments?  Define couple?  Define moment of a couple.  State Varignon’s theorem ( State the principle of moments)  What is the arm of the couple?
  • 37. Additional questions ..  Write the unit of 1.)force, 2.)moment of a force, 3.)couple 5.)moment of a couple and 6.)torque.  State principle of transmissibility.  What are the elements (specifications) of force?  State the triangle law of forces.  State the parallelogram law of forces.  State the polygon law of forces.  What is resolution of forces?  Differentiate between resultant and equilibrant.  Define couple?  State Varignon’s theorem ( State the principle of moments)  List the characteristics of couple?
  • 38. References..  1. R.S.Khurmi : Applied Mechanics & Strength of Materials; S. Chand Publishing  2. M.Chakrabroti : Strength of materials ; S.K Kataria &sons.  3. R.K.Rajput : Strength of Materials ; S. Chand Publishing  4. S.S.Bhavikatti : Strength of Materials ; Vikas Publishing House Pvt Ltd,  5.K.N.A.G.K. Manikanta: Theory of structures –I; Radiant Publishing House