Equilibrium of Rigid Bodies - Engineering Mechanics (Undergraduate Advanced)

Equilibrium is the foundation of all structural and mechanical analysis. This course provides a rigorous study of the equilibrium of rigid bodies in two and three dimensions. It covers reactions, equilibrium equations, constraints, and statical determinacy, supported by extensive worked examples. Engineers, architects, and applied scientists constantly rely on equilibrium principles to design safe, efficient, and reliable systems. From bridges and buildings to machines and vehicles, every stable structure depends on correct modelling of supports, forces, and constraints. Mastery of equilibrium ensures accuracy in analysis and prevents costly or dangerous failures. By completing this course, you will be able to draw free-body diagrams, apply equilibrium equations in 2D and 3D, and classify and analyse different support and constraint conditions. You will understand when a system is properly constrained, over-constrained, or indeterminate, and you will have practical experience solving a wide range of equilibrium problems. This course is intended for undergraduate students in mechanical, civil, and structural engineering, but it is also useful to anyone studying applied mechanics at an advanced level. It provides both a theoretical foundation and practical problem-solving skills valuable to practising engineers, technical instructors, or anyone needing precise understanding of equilibrium in rigid body mechanics.

28

33 hrs

Enrolment valid for 12 months
This course is also part of the following learning tracks. You may join a track to gain comprehensive knowledge across related courses.
MEE 205: Engineering Mechanics - Statics
MEE 205: Engineering Mechanics - Statics
Master the science of structural stability. This programme provides a complete education in engineering statics, covering the analysis of forces, moments, and equilibrium in rigid bodies. It delivers the non-negotiable principles required to design safe and reliable structures. This learning track is for first or second-year undergraduate students in Civil, Mechanical, Aerospace, and Structural Engineering. It is the foundational mechanics course upon which all subsequent design and analysis subjects are built. Analyse the forces within any static structure, from simple trusses to complex machines. You will master free-body diagrams, equilibrium equations, and structural analysis methods. This programme equips you with the core analytical skills for a career in structural, mechanical, or civil design.

Master the science of structural stability. This programme provides a complete education in engineering statics, covering the analysis of forces, moments, and equilibrium in rigid bodies. It delivers the non-negotiable principles required to design safe and reliable structures. This learning track is for first or second-year undergraduate students in Civil, Mechanical, Aerospace, and Structural Engineering. It is the foundational mechanics course upon which all subsequent design and analysis subjects are built. Analyse the forces within any static structure, from simple trusses to complex machines. You will master free-body diagrams, equilibrium equations, and structural analysis methods. This programme equips you with the core analytical skills for a career in structural, mechanical, or civil design.

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GET 207: Applied Mechanics
GET 207: Applied Mechanics
Master the non-negotiable principles of Engineering Mechanics. This track delivers a rigorous, complete programme in statics and dynamics, built to the NUC GET 207 core curriculum. It moves methodically from force systems and equilibrium to the kinematics of rigid bodies and the kinetics of particles. This is the foundation of all structural and mechanical analysis. This programme is for first and second-year undergraduate engineering students. It is an essential requirement for students in Mechanical, Civil, Structural, Aerospace, and Mechatronics engineering. A working knowledge of introductory physics and calculus is assumed. On completion, you will be able to analyse and solve complex problems in statics and particle dynamics. You will draw free-body diagrams, apply equilibrium equations, analyse trusses and frames, and solve motion problems using Newton's laws, work-energy, and momentum methods. This programme prepares you for advanced courses, particularly Mechanics of Materials, and future professional engineering practice.

Master the non-negotiable principles of Engineering Mechanics. This track delivers a rigorous, complete programme in statics and dynamics, built to the NUC GET 207 core curriculum. It moves methodically from force systems and equilibrium to the kinematics of rigid bodies and the kinetics of particles. This is the foundation of all structural and mechanical analysis. This programme is for first and second-year undergraduate engineering students. It is an essential requirement for students in Mechanical, Civil, Structural, Aerospace, and Mechatronics engineering. A working knowledge of introductory physics and calculus is assumed. On completion, you will be able to analyse and solve complex problems in statics and particle dynamics. You will draw free-body diagrams, apply equilibrium equations, analyse trusses and frames, and solve motion problems using Newton's laws, work-energy, and momentum methods. This programme prepares you for advanced courses, particularly Mechanics of Materials, and future professional engineering practice.

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Course Chapters

1. Introduction
5

Welcome to the course and review of fundamental concepts - internal and external forces, equilibrium conditions for rigid bodies, use of free-body diagrams, etc.

Chapter lessons

1-1. Welcome
14:52

Welcome to the course and course outline.

1-2. Idealized models
12:37

Meaning and use of idealized models for the force analysis of rigid bodies.

1-3. Internal and external forces
20:46

Internal and external forces on a rigid body - meaning and when each should be considered.

1-4. Conditions of equilibrium
11:23

Meaning and conditions of equilibrium of rigid bodies.

1-5. Free-body diagrams
22:00

Meaning, use and general procedure for producing free-body diagrams for the force analysis of rigid bodies.

2. 2D Reactions
4
2

Determining force and moment reactions at contacts, connections and supports for a rigid body under the action of co-planar forces - in order to produce its free-body diagram.

Chapter lessons

2-1. Rollers, rockers, etc.
27:43

Reactions at rollers, rockers, frictionless surfaces, tracks and bars.

2-2. Cables, links, pulleys and springs
18:20

Modelling reactions at connections to cables, links or bars, pulleys and springs.

2-3. Pins and rough surfaces
7:05

Modelling reactions at pins and rough surfaces.

2-4. Fixed supports
6:38

Modelling reactions at moment-resisting collars and fixed supports.

3. 2D Equilibrium Equations (1)
1
24

General analysis of equilibrium of rigid bodies in two dimensions.

Chapter lessons

3-1. Procedure
34:50

General equations and procedure for analysis of the equilibrium of a rigid body under the action of co-planar forces.

4. 2D Equilibrium Equations (2)
2
8

Analysis of special cases of equilibrium of rigid bodies in two dimensions - equilibrium under the action of only two or three forces.

Chapter lessons

4-1. Two-force body
14:55

A simplified condition for the equilibrium of a rigid body under the action of only two co-planar forces.

4-2. Three-force body
11:42

A simplified condition for the equilibrium of a rigid body under the action of only three co-planar forces.

5. 2D Constraints and Statical Determinacy
4
1

Different conditions of constraints on rigid bodies in two dimensions and their statical determinacy.

Chapter lessons

5-1. Complete constraints
21:14

When is a two-dimensional structure said to be completely-constrained?

5-2. Partial constraints
10:37

When is a two-dimensional structure said to be partially-constrained?

5-3. Improper constraints
17:27

When is a two-dimensional structure said to be completely-constrained?

5-4. Statical determinacy
15:39

When is a two-dimensional structure statically-determinate?

6. 3D Reactions
6
2

Determining force and moment reactions at contacts, connections and supports for a rigid body under the action of three-dimensional forces - in order to produce its free-body diagram.

Chapter lessons

6-1. Frictionless contacts, cables, etc.
8:36

Reactions at frictionless contacts, cables, springs, etc.

6-2. Rollers
9:19

Reactions at rollers in a guide or on rough surfaces.

6-3. Rough surfaces and ball-and-socket joints
5:27

Reactions at rough surfaces and ball-and-socket joints

6-4. Universal joints and fixed supports
10:22

Reactions at universal joints and fixed supports.

6-5. Hinges
21:26

Reactions at single and double hinges.

6-6. Bearings
20:41

Reactions at single and multiple journal and thrust bearings.

7. 3D Equilibrium Equations
1
12

Analysis of equilibrium of rigid bodies in three dimensions.

Chapter lessons

7-1. Procedure
15:29

General procedure for the analysis of equilibrium of a rigid body under the action of forces in space.

8. 3D Constraints and Statical Determinacy
2

Different conditions of constraints on rigid bodies in three dimensions and their statical determinacy.

Chapter lessons

8-1. Constraints
10:33

When is a three-dimensional structure said to be completely, partially or improperly constrained?

8-2. Statical determinacy
6:42

When is a three-dimensional structure said to statically-determinate?