--- title: Introduction to Vectors --- # Introduction to Vectors. A vector is a physical quantity that can be measured (has magnitude in units) and also operates in a particular direction, unlike a scalar which can only be measured. Examples of vectors include velocity, acceleration, force and momentum. A vector can be represented by a line drawn, such that: - the length of the line represents the

magnitude

of the vetor in a given unit; - the direction of the line represents the

direction

in which the vector operates (or acts). ![vector-representation](https://github.com/xeroxism/myImages/blob/master/FCC_guides/vector-representation.png?raw=true) In the figure above, the displacement of A to B is written as

AB

(

ā

a

). point A is the origin or initial point and the point B is the head or terminal point. This displacement is equivalent to moving a distance

x

horizontally followed by

y

vertically. ### The Modulus of a vector The modulus of a vector is a positive scalar number that gives magnitude of the vector. It is written like this:

| AB |

| a |

or simply

AB

a

. Where;

|AB| =

\sqrt(x 2 + y 2)

### More Information: 1. [Euclidean vector](https://en.wikipedia.org/wiki/Euclidean_vector). 2. [Vector and Vector Arithmetic](http://spiff.rit.edu/classes/phys311.old/lectures/vector/vector.html).