An Active Force Diagram is a visual representation of the forces acting on a system, such as a structure or object. It shows the magnitude and direction of each force, as well as their points of application.
A Free Body Diagram only shows the external forces acting on a system, while an Active Force Diagram also includes internal forces. Internal forces are forces that act within the system, such as tension or compression in a structure.
Virtual Work is a method used to calculate the displacement of a system caused by a force. In Active Force Diagrams, it is used to determine the displacement of a structure or object under the influence of internal forces.
To calculate Virtual Work, the force acting on the system is multiplied by the displacement caused by that force. The sum of all these products is the total Virtual Work.
Active Force Diagrams and Virtual Work are commonly used in structural engineering to analyze the stability and strength of buildings and other structures. They are also used in physics and mechanics to analyze the movements and forces of objects, such as in the design of machinery and vehicles.