Impulse, denoted $\vec{J}$, is a vector quantity defined as the product of an average force ($\vec{F}_{\text{avg}}$) and the time ($\Delta t$) that the force is exerted over.

The magnitude of impulse, $J$, depends on the strength (magnitude) of the force $F_{\text{avg}}$ and the length of time $\Delta t$.

$$J = F_{\text{avg}} \Delta t$$

In real-world scenarios like collisions or explosions, forces often vary rapidly. Instead of tracking the changing force, we use the average force $\vec{F}_{\text{avg}}$. This constant value makes calculation manageable while representing the same total physical effort delivered over the time $\Delta t$.

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