A vector of unit magnitude is called a unit vector . It has the same direction as that of the given vector .
A unit vector of is written as and is read as A cap.
= A Or
where A = magnitude of .
So, a unit vector in a given direction can also be defined as a vector in that direction divided by the magnitude of the given vector.
It has not unit and dimension. It represents direction only.
Example- are the unit vectors along x axis , y axis and z axis respectively.