Impulse and Momentum Calculator
Calculate signed momentum change, impulse, average force and kinetic-energy change from mass, initial/final velocity and interaction time.
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Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Convert the selected mass, velocities and duration to SI. Momentum is mass times signed velocity; impulse is final minus initial momentum. Divide impulse by duration for the average net force during the stated interval.
p=mv; J=Δp=m(vf−vi); Favg=J/Δt
Worked example
A 2 kg object changing from +12 m/s to −3 m/s has impulse −30 N·s. Over 120 ms, its average net force is −250 N.
Assumptions and input details
Velocity and all signed results follow the direction convention you choose. Duration must be positive. The average net force is the time-average consistent with the entered impulse; peak force and force-time shape are not inferred. Kinetic-energy change is reported separately because impulse and energy are different physical quantities. External forces, rotation, deformation and multi-object collision details are not modeled.
References: OpenStax: linear momentum and force
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
The 19 mass definitions distinguish avoirdupois and troy measures, metric and regional measures. Japanese kin is 600 g; mainland Chinese shijin is 500 g.
Regional measures are not interchangeable merely because their names look similar. This is a documented selection, not a claim to include every historical unit.
NIST measurement tables · Japanese traditional units · Mainland China and Hong Kong unit distinctions
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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