Triangular law and parallelogram law of addition

What is the use of triangular & parallelogram law?

Now, we know that adding scalar quantities is very simple, just we need to add it normally but for vector quantities such as force, we cannot perform addition like this. So, to add the vector quantity we use the triangular law and parallelogram law. 

Remember that this two law can be used only for the addition of 2 force or 2 vector quantity.

Triangular law for addition: 

If two forces acting simultaneously on a body such that they can be represented by two adjacent sides of a triangle taken in same order, then their resultant will be equal to the third closing side of triangle taken in opposite direction or order.

Parallelogram law for addition:

If two vectors are represented by two adjacent sides of parallelogram then the diagonal through intersection represents their resultant.


These are the graphical method to add vector. we can also use analytical method for the addition of vector.