Calculadora de Impulso e Momento
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
J = F·Δt
About this calculator
The Impulse and Momentum Calculator is an online tool that allows you to calculate the impulse (J) applied to an object or the change in its linear momentum (Δp). Impulse is defined as the product of the applied force (F) and the time interval (Δt) during which the force acts. The fundamental formula is J = F·Δt, and impulse equals the change in linear momentum, i.e., J = Δp. This calculator is useful for physics students, engineers, and professionals solving problems involving collisions, launches, and changes in momentum.
How it works: you enter the force (in newtons) and the time interval (in seconds) to obtain the impulse. Alternatively, if you have the change in momentum, you can calculate the required force or time. The calculator uses the direct relationship between impulse and momentum, assuming constant force during the interval. Remember that linear momentum is the product of mass and velocity (p = m·v), and the change in momentum is m·Δv.
When to use: this calculator is ideal for situations such as studying elastic and inelastic collisions, acceleration of objects by constant forces, vehicle braking, impacts in sports (e.g., a ball being kicked), and any problem where a force acts over a specific time. For example, calculating the average force exerted by an airbag on a driver during a collision, given the impact time and the change in velocity.
Common precautions: ensure the force is constant during the time interval; otherwise, the calculation provides only the average impulse. Check units: force in newtons (N), time in seconds (s), and impulse in N·s (equivalent to kg·m/s). Remember that force and momentum are vector quantities; this calculator works with scalar values, assuming force and motion are in the same direction. For two-dimensional problems, decompose the quantities into components.
Frequently asked questions
What is the difference between impulse and linear momentum?
Impulse is force applied over a time interval, while linear momentum is the quantity of motion of an object (mass times velocity). Impulse causes a change in linear momentum.
Can I use this calculator for variable forces?
For variable forces, impulse is calculated as the area under the force-time curve. This calculator assumes constant force; if you use the average force, it gives the average impulse.
What units should I use?
Use force in newtons (N) and time in seconds (s). Impulse will be given in N·s, which is equivalent to kg·m/s.
How do I calculate the change in momentum if I have mass and velocity?
The change in momentum is m·Δv, where m is mass and Δv is the change in velocity. You can calculate Δp and then use J = Δp to find the impulse.
Is this calculator useful for collisions?
Yes, it is very useful for collisions. In a collision, the impulse exchanged between objects equals the change in momentum of each, provided the force acts over a known time.