What is linear momentum?

Linear momentum (p) is the product of an object's mass (m) and its velocity (v): p = mv. It is a vector quantity measured in kilogram-meters per second (kg·m/s) in SI units. A more massive or faster-moving object has greater momentum.

What is impulse and how does it relate to momentum?

Impulse (J) is the change in momentum produced by a force applied over a time interval: J = F×Δt = Δp. It is measured in newton-seconds (N·s), which equals kg·m/s. A larger force or longer contact time produces a greater change in momentum.

What is the law of conservation of momentum?

In an isolated system with no external net force, the total momentum before and after a collision or explosion remains constant. This is the basis for analyzing collisions: p_before = p_after.

What units does this calculator support?

Mass: kilograms (kg), grams (g), pounds (lb), slugs. Velocity: m/s, km/h, mph, ft/s. Momentum output is shown in kg·m/s, g·cm/s, lb·ft/s, and slug·ft/s. Impulse force in N and lbf; time in seconds, milliseconds, and minutes.

How does this differ from force?

Force (F = ma) is mass times acceleration and measures the rate of change of momentum. Momentum (p = mv) is mass times velocity. Impulse ties both together: J = F×Δt = Δp = mΔv.

Momentum Calculator

Name: Momentum Calculator
Availability: InStock
Author: Nham Vu

Calculate linear momentum (p = mv) or impulse (J = F×Δt). Solve for any unknown given two known values, with full metric and imperial unit support.

Momentum Calculator

Mode

Solve for

Mass

Velocity

Enter two known values on the left to compute the result.

p = mv • J = FΔt

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Summary

Calculate linear momentum (p = mv) or impulse (J = F×Δt). Solve for any unknown given two known values, with full metric and imperial unit support.

How it works

Select the tab: Momentum (p = mv) or Impulse (J = F×Δt).
Choose what you want to solve for using the "Solve for" selector.
Enter the two known values and pick their units.
The result appears instantly with unit conversions and a worked example.
Click any conversion card to copy that value to your clipboard.

Use cases

Solve physics homework problems on linear momentum and conservation laws.
Calculate the impulse delivered by a force over a time interval.
Convert momentum between SI units (kg·m/s) and imperial units (lb·ft/s).
Verify collision or explosion calculations in mechanics coursework.
Determine the mass or velocity of an object from its known momentum.

Frequently Asked Questions

Last updated: 2026-06-09 · Reviewed by Nham Vu