Impulse is fundamentally related to changes in momentum; it is defined as the product of the force applied to an object and the duration of time over which that force acts.

In physics, impulse quantifies the overall effect of a force acting on a body during a specific time interval. It is mathematically expressed as:

The unit of impulse is the Newton-second (N·s), which is equivalent to a kilogram-meter per second (kg·m/s). Notably, this unit matches that of momentum, highlighting the intrinsic connection between impulse and momentum. Specifically, impulse is directly linked to the change in momentum of an object.

The principle of impulse and momentum articulates that the change in momentum of an object is equal to the impulse imparted to it. This principle is derived from Newton’s second law of motion, which states that the force acting on an object equals the mass of the object multiplied by its acceleration:

By multiplying both sides of this equation by the time duration over which the force acts, we obtain the relationship between impulse and change in momentum:

where $\Delta p$ denotes the change in momentum.

This relationship is observable in everyday scenarios. For instance, when you kick a football, the force exerted by your foot on the ball over a certain period of time (the impulse) results in a change in the ball’s momentum, causing it to move. The strength of your kick (the magnitude of the force) and the duration of contact between your foot and the ball (the time) both contribute to the extent of the change in momentum.

In summary, impulse is a vital concept for understanding how forces influence the motion of objects. It serves as a bridge between the force applied, the time duration of that force, and the resulting change in momentum. This relationship is fundamental in the field of physics and has numerous applications, ranging from sports science to rocket propulsion.