Kinematics

Describing motion

Displacement $s$ — distance in a stated direction (vector, m).
Velocity $v$ — rate of change of displacement (vector, m s⁻¹): $v = \dfrac{\Delta s}{\Delta t}$.
Acceleration $a$ — rate of change of velocity (vector, m s⁻²): $a = \dfrac{\Delta v}{\Delta t}$.