1. VECTOR FORMULAS  A vector is an object that has both a magnitude and a direction. In Geometrically, we can picture a vector as a directed line segment, whose length is the magnitude of the vector and with an arrow indicating the direction.

2. TRIANGULAR LAW OF ADDITION  If two forces Vector A and Vector B are acting in the same direction, then its resultant R will be the sum of two vectors.

3. Parallelogram Law of Addition If two forces Vector A and Vector B are represented by the adjacent sides of the parallelogram, then their resultant is represented by the diagonal of a parallelogram drawn from the same point. Formula for Parallelogram law of Addition: R ⃗ =A ⃗ +B ⃗

4. Triangle law of forces ‘ If two forces acting at a point can be represented both in magnitude and direction, by the two sides of a triangle taken in tip to tail order, the third side of the triangle represents both in magnitude and direction the resultant force F, the sense of the same is defined by its tail at the tail of the first force and its tip at the tip of the second force’. Resultant of two forces acting at a point

5. ‘If two forces acting at a point are represented in magnitude and direction by the two adjacent sides of a parallelogram, then the resultant of these two forces is represented in magnitude and direction by the diagonal of the parallelogram passing through the same point. Parallelogram law of forces point

6. Moment of A Force  The applied force can also tend to rotate the body about an axis in addition to motion. This rotational tendency is known as moment.  This is a vector quantity having both magnitude and direction. Moment is the tendency of a force to make a rigid body to rotate about an axis.

7.  Moment Center: This is the position of axis on co-planar system. (A).  Moment Arm: Perpendicular distance from the line of action of the force to moment center. Distance AB = d.