Impulse

Impulse is the product of the force ($\vec{F}$) and change in time ($\Delta t$).  $$Impulse = \vec{F}\Delta t$$The impulse differs from the Momentum Principle in that it is distinct in forces.  The change in momentum ($\Delta\vec{p}$) is equal to the sum of the impulses applied, or:  $$\Delta\vec{p} = \sum\limits_{i=1}^n \vec{F}_i\Delta t$$