# Kinetic energy and momentum

To the mobile version
 Kinetic energy Ekin = J = kg m/s² kJ cal kcal Velocity v = m/skm/h ft/smi/h Mass m = gkgozlb Momentum s = N s = kg m/sg cm/skg km/hkg mi/h

Rounding: significant digits.
Decimal sign:

The kinetic energy of an object is the energy it posseses due to its motion. It is defined as the work needed to accelerate the object of a given mass to its velocity. There are the following equations in classical mechanics for kinetic energy and momentum.

Ekin = ½ m v²
P = m v

With this calculator you can calculate the kinetic energy Ekin and the momentum P of a mass point from a given mass m and a given velocity v. Calculations vice versa are also possible.

Usage: Always choose the correct unit in the corresponding pull-down-menu before you type a value. Type the given values into the corresponding fields. After a mouse click on any free space of the window or the "calculate"-button the calculation is performed. The fields with the input quantities have a light green background, the background of the output quantities is colored pink.
For another calculation with a value that has been calculated before, click on the radio button in front of the value. The lines with this quantity will be recolored light green and become input values for the next calculation. The calculation is always performed with the two quantities changed last.
Click on the "reset"-button to reset the calculation.

Example Together with his bicycle a cyclist has a mass of 85 kg. What must be his velocity, so that his kinetic energy amounts 1 kcal (or, to which speed must he accelerate from zero, that, without considering any friction etc., the work done amounts 1 kcal)?
Type the total mass (85 kg) into the corresponding field. As unit for the kinetic energy choose kcal from the pull-down menu and type the value of 1 into the field. After the next mouse click on any free space of the window or the "calculate"-button you can read the value of the velocity (9.9 m/s).
In the pull-down menu for the velocity unit you could also choose another unit (e.g. 35.7 km/h).

Remarks: