The principle of work and kinetic energy (also known as the work-energy principle) states that the work done by all forces acting on a particle (the work of the resultant force) equals the change in the kinetic energy of the particle. This definition can be extended to rigid bodies by defining the work of the resultant torque and rotational kinetic energy.
The work W done by the resultant force on a particle equals the change in the particle's kinetic energy ,
- ,
where and are the speeds of the particle before and after the change and m is its mass.
Read more about this topic: Work (physics)
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