Kinetic Energy - Yousef's Notes

Defining the function $$ K=\frac{1}{2}mv^2 $$ , called kinetic energy, the Work-energy Theorem reads $$ W=(K_2-K_1)=\Delta K $$

Properties

Same units as work
the kinetic energy of a particle is a scalar quantity; it depends on only the particle’s mass and speed
Kinetic energy can never be negative, and it is zero only when the particle is at rest.
the kinetic energy can be though of as the total work need to accelerate a body from rest to its present speed.
Power can be interpreted as the rate at which the kinetic energy of the system changes.
So work done on a body alters the kinetic energy. Let’s be careful though, the total kinetic energy of a composite system can change even if no work is done.