What is the momentum of an object of mass $m$, moving with a velocity $v$?

Newton's second law of motion gives us a measure of

Using the second law of motion,derive the relation between force and acceleration. $A$ bullet of $10 \, g$ strikes a sandbag at a speed of $10^3 \, m \, s^{-1}$ and gets embedded after traveling $5 \, cm$. Calculate:
$(i)$ The resistive force exerted by the sand on the bullet.
$(ii)$ The time taken by the bullet to come to rest.

What is the mathematical formula and $SI$ unit of momentum?

What is the force required to accelerate a $2 \, kg$ mass by $5 \, m s^{-2}$ (in $, N$)?

Which would require a greater force $-$ accelerating a $2 \ kg$ mass at $5 \ m s^{-2}$ or a $5 \ kg$ mass at $3 \ m s^{-2}$?