Use the Momentum Calculator
What is a Momentum Calculator? It is a browser-based tool that finds linear momentum from mass and velocity using p = mv, showing the formula, every intermediate value, and supported units.
Use this calculator to find linear momentum with p = m × v. Enter mass and velocity, choose their units, and click Calculate. The tool converts the values before multiplying and shows the result with its calculation steps.
Enter Mass, Velocity, and Units
- Enter a mass in Mass (m) and choose Mass unit: Kilograms (kg), Grams (g), Pounds (lb), Slugs, or Metric tons (t).
- Enter a velocity in Velocity (v) and choose Velocity unit: Meters per second (m/s), Kilometers per hour (km/h), Miles per hour (mph), or Feet per second (ft/s).
- Mass must be greater than zero. Velocity may be positive, negative, or zero.
Calculate, Reset, Copy, or Download
- Enter the mass and velocity, then select their units.
- Click Calculate to display momentum and the formula steps.
- Click Reset to clear both inputs, restore Kilograms (kg) and Meters per second (m/s), and hide the result.
- After a result appears, click Copy result to copy the plain-text result and steps, or click Download result (.txt) to download them as a text file.
Input Validation and Accepted Number Format
Both fields are required. Mass must be greater than zero, while velocity can be negative or zero. Enter a signed decimal such as -12.5 or 20. The input parser rejects exponential notation, a leading plus sign, comma-separated values, and other text that does not match its signed decimal format.
Each mass or velocity value must have an absolute value of no more than 1e12. The calculator also checks that the final momentum is finite and shows an error instead of displaying an unrepresentable result.
Calculation Scope and Limitations
The tool converts the selected units and applies p = m × v. A negative velocity produces a signed negative scalar result. It does not calculate 2D or 3D vector components, infer a missing mass or velocity, or model collisions, impulse, or momentum conservation between multiple objects.
The output is not presented as certified engineering, coursework, or professional advice.
Privacy and Page-Level Data Handling
The calculation script processes the entered mass and velocity values locally and does not transmit those values. The page also loads analytics, and its subscription form sends an email address when you use it.
Frequently Asked Questions
What is the formula for linear momentum?
Linear momentum equals mass times velocity: p = m × v. It describes the quantity of motion an object has, and its direction is the same as the velocity's direction.
What units does this calculator support?
Enter mass in kilograms, grams, pounds, slugs, or metric tons. Enter velocity in meters per second, kilometers per hour, miles per hour, or feet per second. Results are shown in kg·m/s, lb·ft/s, slug·ft/s, and g·cm/s.
Can velocity be negative?
Yes. A negative velocity produces a negative momentum in the same signed direction, meaning the object is moving opposite to the direction you defined as positive. Mass, however, must be greater than zero.
What is the difference between momentum and kinetic energy?
Momentum (p = m × v) is a vector that scales linearly with velocity, while kinetic energy (KE = 1/2 mv²) is a scalar that scales with the square of velocity. Momentum is conserved in collisions; kinetic energy is only conserved in elastic collisions.
Does this calculator model collisions or impulse?
No. It applies p = m × v to the values you provide. It does not model collisions, impulse, or momentum conservation between multiple objects.