User:Invisire

Retardation
It is the negative acceleration (the change of velocity upon time) and is referred in m/sxs (metre per second square). It is often mistaken by thinking it have a unique equation. In fact, it do not have any.

It is formulated by the formula of acceleration i.e. a= v-u/t (acceleration= final velocity - Initial velocity / time)

After solving with this equation, if the answer contains negative sign, then it is called retardation or deceleration.