Momentum Calculator

Calculate momentum using p = m × v. Enter mass and velocity to find linear momentum in kg·m/s.

Mass (kg)

Velocity (m/s)

Enter mass and velocity to calculate momentum.

Momentum Formula

p = m × v

Where:

p = momentum (kg·m/s)
m = mass (kg)
v = velocity (m/s)

Example

Problem: A 1500 kg car travels at 20 m/s. What is its momentum?
Solution: p = 1500 × 20 = 30,000 kg·m/s

Conservation of Momentum

In an isolated system with no external forces, total momentum is conserved. This is fundamental to understanding collisions:

m₁v₁ + m₂v₂ = m₁v₁' + m₂v₂'

Impulse-Momentum Theorem

The impulse (force × time) equals the change in momentum:

F × Δt = Δp = m × Δv

FAQ

Can momentum be negative?

Yes. Momentum is a vector quantity. Negative momentum indicates motion in the negative direction (opposite to the defined positive direction).

What's the difference between momentum and kinetic energy?

Momentum (p = mv) is a vector and scales linearly with velocity. Kinetic energy (KE = ½mv²) is a scalar and scales with the square of velocity. Two objects can have the same momentum but different kinetic energies.

Why is momentum important in collisions?

Conservation of momentum allows us to predict the outcomes of collisions. In all collisions (elastic and inelastic), total momentum is conserved, while kinetic energy is only conserved in elastic collisions.

Last updated: 2026-08-08