Enter the final kinetic energy, the change in mass, and the change in velocity into the calculator to determine the Initial Kinetic Energy. 

Initial Kinetic Energy Formula

The following equation is used to calculate the Initial Kinetic Energy.

KEi = KEf - 1/2*dm*dV^2
  • Where KEi is the Initial Kinetic Energy (Joules)
  • KEf is the final kinetic energy (Joules)
  • dm is the change in mass (kg)
  • dV is the change in velocity (m/s)

What are the units for Initial Kinetic Energy?

The most common units for Initial Kinetic Energy are Joules.

How to Calculate Initial Kinetic Energy?

Example Problem:

The following example problem outlines the steps and information needed to calculate the Initial Kinetic Energy.

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

Next, determine the change in mass. For this problem, the change in mass is measured to be 3 (kg).

Next, determine the change in velocity. In this case, the change in velocity is found to be 6 (m/s).

Finally, calculate the Initial Kinetic Energy using the formula above: 

KEi = KEf – 1/2*dm*dV^2

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

KEi = 500 – 1/2*3*6^2 = 446 (Joules)