Vector

What is a vector?

A vector is a physical quantity which has a direction. Velocity and acceleration are examples of vector.

Types of vector:

Null vector or zero vector:A vector whose initial and terminal points are coincident is called a zero or null or a void vector.  a  = AB is the presentation of null vector.

Proper vector:Vectors other than the null vector are called proper vectors.

Unit vector:A type of  vector whose modulus is unity, is called a unit vector.

Negative of a vector:

  
The negative of a vector AB is a vector whose magnitude  is the same as that of vector AB but has the direction opposite to it.

Thus AB represents the vector of vectors a

= > BA represents −a