Is momentum the same as kinetic energy?

No. Momentum is directional and depends linearly on velocity; kinetic energy is scalar and depends on speed squared.

What does negative velocity mean?

It means motion in the negative direction of the selected axis, not an invalid input.

Impulse is measured in newton-seconds, which are equivalent to kg.

Calculate linear momentum, impulse, and one-dimensional elastic or perfectly inelastic collision outcomes.

What to calculate

Linear momentum Elastic collision Inelastic collision Impulse

Mass

Velocity

Quick scenarios

Linear momentum

25,000

SI mass: 1,500 kg; velocity: 16.667 m/s; result: 25,000 kg·m/s

Kinetic energy

208,333.3 J

in N·s

25,000

Half velocity

8.333 m/s

English intent combines the classroom calculation with impulse and simple one-dimensional collision models.

p = m v

p is linear momentum, m mass and v velocity along the chosen axis.

J = F Δ t = Δ p

J is impulse, equal to the change in momentum for the chosen interval.

One-dimensional model

Elastic and perfectly inelastic modes are ideal 1D models. Real crashes, safety analysis and ballistics need expert models and data.

Calculations are based on the listed reference sources. Links open in a new tab.

Updated: June 2, 2026

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