Unit Vectors
A unit vector is a vector of unit magnitude and a particular direction.
- They specify only direction. They do not have any dimension and unit.
- In a rectangular coordinate system, the x, y and z axes are represented by unit vectors, î,ĵ andk̂
- These unit vectors are perpendicular to each other.
- |î| = |ĵ | = |k̂| = 1

In a 2-dimensional plane, a vector thus can be expressed as:
- A = Ax î +Ay ĵ where, Ax = A cosθ and Ay = A sinθ
- A =

