Changes

The '''velocity''' of an object is the rate of change of its [[displacement]], and direction of the change. If the position of an object is some [[function]] of [[time]], then the velocity is the [[derivative]] of that function:

The '''velocity''' of an object is the rate of change of its [[displacement]] and direction of the change.  In other words, it is a combination of both speed and direction. If the position of an object is some [[function]] of [[time]], then the velocity is the [[derivative]] of that function:

:<math>v(t)={\mathrm{d}x \over \mathrm{d}t}</math>

:<math>v(t)={\mathrm{d}x \over \mathrm{d}t}</math>