Velocity is the rate o chynge o the poseetion o an object, equivalent tae a specification o its speed an direction o motion, e.g. 60 km/h tae the north. Velocity is an important concept in kinematics, the branch o classical mechanics which describes the motion o bodies.
Velocity is a vector pheesical quantity; baith magnitude an direction are required tae define it. The scalar absolute value (magnitude) o velocity is cried "speed", a quantity that is measured in metres per seicont (m/s or m·s−1) in the SI (metric) seestem. For example, "5 metres per seicont" is a scalar (nae a vector), whauras "5 metres per seicont east" is a vector.
If thare is a chynge in speed, direction, or baith, then the object haes a chyngin velocity an is said tae be unnergangin an acceleration.