Question

define retardation and give the formula to find retardation​

Answer 1

Answer:

"Retardation means negative acceleration. ... So formula will be the same as that of acceleration. As acceleration can be defined as the rate of change of velocity i.e. mathematically: a= (v-u)/t. Where v = final velocity, u= initial velocity & t= time taken to change the velocities.

Answer 2

Answer:

Negative acceleration ( Acceleration is the rate of speed in a unit time) is called retardation.Its SI unit is m/s^2

The formula to find acceleration and retardation is same i.e:

$a = \frac{(v - u)}{t}$

In acceleration v > u and in retardation v < u where v is the final velocity and u is the initial velocity.So hence,if acceleration is negative so it is called retardation.