A system can be brought to equilibrium by applying another force equal to the resultant force in magnitude, but opposite in direction is called as Equilibrant.

Find the retardation with which a train moving at $108 \mathrm{km}/\mathrm{hr}$ is brought to rest in $12$ seconds.

Two similar trucks are moving with the same velocity on a road. One of them is loaded while the other is empty. Which of the two will require a larger force to stop it?

A body moves with constant velocity of $20 \mathrm{m} {\mathrm{s}}^{-1}$. The mass of body is $2 \mathrm{kg}$. The unbalanced force acting on the body is _____ $\mathrm{N}$.