Impulse Calculator
Calculate impulse from force and time interval.
Impulse Formula
J = FΔt, equal to the change in momentum.
What Is Impulse?
Impulse measures the effect of a force acting over a time interval. For a constant force, J = FΔt. The impulse-momentum theorem states that impulse equals the change in momentum of the object.
Example Calculation
A constant 80 N force acting for 0.25 s produces an impulse of 80 × 0.25 = 20 N·s. The object’s momentum changes by the same 20 kg·m/s.
Factors and Interpretation
Increasing force or contact time increases impulse. This is why airbags and padding reduce peak force: they can increase the stopping time while producing the impulse needed to change momentum. If force varies strongly with time, the true impulse is the area under the force-time curve rather than simply one constant force multiplied by time.
Frequently Asked Questions
Is impulse a force?
No. Impulse is force multiplied by time and has units N·s.
How is impulse related to momentum?
Impulse equals the change in momentum.
Can impulse be negative?
Yes. Its sign depends on the chosen direction of the applied force.
Related Tools
Formula and Practical Limits
Impulse equals the change in momentum and, for constant force, J = FΔt. When force varies with time, impulse is the area under the force-time curve rather than simply peak force multiplied by duration.