ABSTRACT
A force can be depicted by its magnitude, direction, and point of application. A force system or a system of forces refers to several forces acting on a body. Forces which lie on a single plane are called coplanar forces or coplanar force system. When all the forces pass through a common point, the force system is known as concurrent force system and forces are known as concurrent forces. Like parallel forces are parallel to each other with their lines of action in the same direction. Unlike parallel forces are parallel to each other with their lines of action in different directions. Polygon law of forces is an extension of triangle law of forces and is used to determine the resultant of more than two concurrent forces. A number of forces acting on a particle are said to be in equilibrium when their resultant force is zero.
