Last updated October 5, 2026 · Report an error
Momentum captures something kinetic energy doesn't — a direct, linear measure of how hard it is to stop a moving object, central to understanding collisions and impacts. This calculator finds the momentum of a moving object from its mass and velocity, with a full step-by-step solution.
How it works
Enter the object's mass and velocity. The calculator applies the standard momentum formula, p = mv, to find the result in kilogram-meters per second.
- Enter mass (kg).
- Enter velocity (m/s).
- Click Calculate to see your results.
Examples
A 10 kg object moving at 5 m/s
This has a momentum of 50 kg·m/s.
Who should use it
- Solving physics homework or exam problems involving momentum.
- Analyzing collision scenarios in physics or engineering coursework.
Industry applications
- Physics and engineering education
- Automotive safety and collision analysis
Advantages
- Uses the exact standard momentum formula.
- Shows the full calculation for a clear, verifiable result.
Limitations
- Calculates linear momentum only — angular momentum for rotating systems requires a different formula.
Common mistakes to avoid
- Confusing momentum (mass times velocity) with kinetic energy (½ mass times velocity squared) — they use different formulas and units.
- Ignoring the sign of velocity, which matters for momentum's direction in problems involving multiple objects.
Best practices
- When working with multiple objects, keep a consistent sign convention for direction to correctly track total momentum in a system.
Tips
- Momentum problems often involve conservation across a system (like two colliding objects) — this calculator finds one object's momentum, which you can then combine with others for a full conservation-of-momentum problem.
Frequently asked questions
Yes, with no signup and no limit on how many calculations you run.
Momentum scales linearly with velocity (double the speed, double the momentum), while kinetic energy scales with velocity squared (double the speed, quadruple the energy) — they capture different physical effects of motion.
Momentum is a vector quantity, so a negative velocity (representing motion in the opposite direction) produces a negative momentum, indicating direction as well as magnitude.
Total momentum is conserved in a closed system during a collision, which is the basis for calculating post-collision velocities in physics problems.