Kinetic Energy


Although the velocity is a vector quantity (has both a magnitude and a direction), the kinetic energy is a scalar quantity that is related only to the magnitude squared of the velocity and not to its direction.  The kinetic energy is therefore a state property since it depends only on the velocity magnitude and not the path taken to reach the current velocity.

Kinetic energy is related to the velocity or motion of a system of particles.

The kinetic energy of a fixed system of particles (i.e. closed system) is defined by the equation


where m is the mass and V is the velocity of the system.  The KE is a state variable in that it doesn’t matter how the system achieved the velocity.   





Learning Objectives:

Define kinetic energy.  Compute kinetic energy given the mass and velocity magnitude.