Difference Between Acceleration and Retardation
Acceleration and retardation are two words to describe the motion of objects. Both these words tell us that there is some change in the velocity of the object which is moving. If there is no change in the velocity then there is no acceleration. For example, if you are driving at a speed of 40 km/h and do not use the accelerator of your car and even do not slow down then there is neither acceleration nor retardation.
The rate, at which the velocity of an object changes in comparison to per unit of time, is known as acceleration. We can understand it by Newton’s law of motion which says that the difference between the initial and final velocity per unit time is acceleration.
v=u+ at, therefore
a= (v-u)/t
If we take an example then the best one would be to understand through the one when you throw a stone up in the air. When you throw the stone it has some initial velocity but when it starts coming back then the point from where it starts coming back, its final velocity is zero. But this same point it point of initial velocity for the downward journey of the stone. Here it will have some final velocity. In both the cases the stone experiences acceleration and retardation.