impulsi

Impulsi is the Italian plural of impulso (impulse) and can refer to multiple instances of impulse in physics and engineering. In physics, an impulse is the short-term force acting on a body that changes its momentum. The impulse J is defined as the integral of force over the time interval of interaction: J = ∫ F dt. It equals the change in linear momentum p, so J = Δp = m Δv. The direction of J matches the force.

For a constant force F acting for a duration Δt, J = F Δt. The unit is newton-second (N·s). The resulting velocity change is Δv = J / m. Impulses occur in everyday phenomena such as collisions, kicks, or thrusts, and provide a compact description of transient forces.

In signal processing and systems theory, impulse refers to an idealized input that excites a system at a single moment. The mathematical impulse is the Dirac delta function δ(t), zero except at t = 0 and with unit integral. The system’s response to an impulse is its impulse response h(t), and many inputs are decomposed by convolution with h(t). In discrete time, the unit impulse δ[n] plays a similar role.

Other uses include brief electrical or biological signals described as impulses, such as nerve impulses in physiology, where impulses are rapid spikes that propagate along neurons. See also impulse (physics), Dirac delta function, and impulse response.