Physics - Center of Mass Question with Solution | TestHub

Impulse is defined as the product of the average force and the time interval over which the force acts. For a constant force $F$ acting for a duration $t$, the impulse $J$ is given by: $$J=F\cdot t$$

According to the impulse-momentum theorem, this impulse is also equal to the change in momentum of the body. Since the body starts from rest, its initial momentum is zero. The final momentum will be $mv$, where $v$ is the final velocity. So, $J=mv-0=mv$.