velocity is a vector expression of the displacement that an object or particle undergoes with respect to time . the standard unit of velocity magnitude (also known as speed ) is the meter per second (m/s). alternatively, the centimeter per second (cm/s) can be used to express velocity magnitude. the direction of a velocity vector can be expressed in various ways, depending on the number of dimensions involved.
for eg- '5 metres per second' is a scalar (not a vector), whereas '5 metres per second east' is a vector.