Impulse and Momentum Calculator
Calculate impulse from force and time, and the resulting change in velocity of a given mass.
How it works
J = F · t · J = Δp = m · Δv → Δv = J / m
Impulse is the effect of a force applied over time, and it equals the change in momentum it produces. A small force over a long time can deliver the same impulse as a large force over a brief instant. This is why airbags and crumple zones extend the collision time — the momentum change is fixed, so stretching the time reduces the peak force.
Worked example
A 200 N force acting for 0.5 s gives an impulse of 200 × 0.5 = 100 N·s. On a 10 kg mass that changes the velocity by 100 ÷ 10 = 10 m/s.
Sources: Impulse (physics) — Wikipedia
Frequently asked questions
What is the impulse-momentum theorem?
It states that the impulse on an object equals its change in momentum: F·t = m·Δv. This links the force history of a collision directly to the change in motion it causes.
Why do airbags reduce injury?
They lengthen the time over which your momentum is brought to zero. Since the impulse (momentum change) is fixed, a longer stopping time means a smaller peak force on the body.
What are the units of impulse?
The newton-second (N·s), which is identical to the kilogram-metre per second (kg·m/s), the unit of momentum. That equivalence is the impulse-momentum theorem in unit form.
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