This chapter introduces the principle of virtual work and how it can be used to determine the equilibrium configuration of connected rigid bodies. It defines work and virtual work, and establishes the potential energy function. The chapter outlines applying the principle of virtual work to particles, rigid bodies, and connected systems to investigate equilibrium and stability, using the potential energy criterion.

1. Chapter 11:
Virtual Work
Engineering Mechanics: Statics

2. Chapter Objectives
To introduce the principle of virtual work and
show how it applies to determining the
equilibrium configuration of a series of pin-
connected members.
To establish the potential energy function and
use the potential energy method to
investigate the type of equilibrium or stability
of a rigid body or configuration.

3. Chapter Outline
Definition of Work and Virtual Work
Principle of Virtual Work for a Particle and
a Rigid Body
Principle of Virtual Work for a System of
Connected Rigid Bodies
Conservative Forces
Potential Energy

4. Chapter Outline
Potential-Energy Criterion for Equilibrium
Stability of Equilibrium