Calculate kinetic energy, mass, or momentum from any two known values using energy, mass, and momentum units like joules, kilograms, and kg·m/s.

Energy To Momentum Calculator

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Momentum from Energy Formula

The following equation is used to calculate the Momentum from Energy.

p = SQRT( 2*KE / m) * m
  • Where p  is the Momentum from Energy (m/s*kg)
  • KE is the total kinetic energy (Joules)
  • m is the mass (kg)

To calculate momentum from energy, multiply the energy by 2, divide by the mass, take the square root of this result, and finally, multiply by the mass.

Energy to Momentum Conversion Table (Non-relativistic; assumes mass m = 1.00 kg)
Energy (J) Momentum (kg·m/s) Momentum (g·cm/s) Momentum (lb·ft/s)
0.51.0001000007.233
11.41414142110.229
22.00020000014.466
53.16231622822.873
104.47244721432.347
206.32563245645.746
5010.000100000072.330
10014.1421414214102.289
20020.0002000000144.660
50031.6233162278228.730
100044.7214472136323.470
200063.2466324555457.456
5000100.00010000000723.301
10000141.421141421361022.890
20000200.000200000001446.602
50000316.228316227772287.295
100000447.214447213603234.703
200000632.456632455534574.560
5000001000.0001000000007233.010
10000001414.21414142135610228.900
Non-relativistic relation: p = √(2 m E). Values assume m = 1.00 kg. Momentum unit factors: 1 kg·m/s = 100000 g·cm/s = 7.23301 lb·ft/s.

What are the units for Momentum from Energy?

The most common units for Momentum from Energy are m/s*kg.

How to Calculate Momentum from Energy?

Example Problem:

The following example problem outlines the steps and information needed to calculate the Momentum from Energy.

First, determine the total kinetic energy. In this example, the total kinetic energy is determined to be 500 (Joules).

Next, determine the mass. For this problem, the mass is measured to be 12 (kg).

Finally, calculate the Momentum from Energy using the formula above: 

p = SQRT( 2*KE / m) * m

Inserting the values from above and solving the equation with the imputed values gives: 

p = SQRT( 2*500/ 12) * 12 = 109.54 (m/s*kg)