The basic knowledge of various kinds of forces and motion is highly desirable for engineering and practical applications. Newton’s laws of motion define and gives the expression for the force. Force is a vector quantity and can be combined according to the rules of vector algebra. A force can be graphically represented by a straight line with an arrow, in which the length of the line is proportional to the magnitude of the force and the arrowhead indicates its direction.

Fig: Concurrent Forces

**Concurrent Forces:** A force system is said to be concurrent if the lines of all forces intersect at a common point.

Concurrent means that the forces crisscross throughout a single point. In a concurrent force organism, all forces pass through a general point. If all forces acting on object intermingle at one point. Consequential of these forces might or might not be zero. If the forces are having a regular line of action, then they are known as collinear whereas if the forces intersect at a regular point, then they are known as concurrent.

So, Concurrent forces are two or more forces whose lines of accomplishment intersect at a similar point to cause rotation. The forces do not essentially have to be applied.

- If forces are concurrent, we can add them together as vectors to get consequential.
- If the body is not accelerating, it must be instability, so that means the consequential is zero.
- For concurrent forces, the body is a point.
- So for concurrent forces in symmetry, the forces should all add up to give zero.

Fig: Coplanar Forces

**Coplanar Forces**: A force system is said to be coplanar if the lines of the action of all forces lie in one plane.

A coplanar force means the forces in a plane. Coplanar force structure refers to the number of forces which stay in a similar plane. If a body is beneath the action of numerous forces and all the forces lie in similar plane then they are said to be coplanar forces. So, when some forces act on a body, then they are called a force system or a system of forces. It is also stated as the number of forces in a structure which remains in a single plane. Now, we can say, in a system in which all the forces lie in a similar plane, it is known as a coplanar force system. This force system can be concurrent, parallel and non-concurrent and non-parallel.