Kinetic Energy

Kinetic energy represents the energy associated with the motion of an object. It is defined as:

K ≡ mv² / 2 for a point mass and $K={1 \over 2}mV^{2}+{1 \over 2}I\omega ^{2}$ for a rigid body, where I is the body's moment of inertia and omega is the body's angular velocity.

The change of kinetic energy is equal to the total work done on it by the resultant of all forces acting on it. For a point mass this can be expressed as:

ΣW = ΔK = mv_f² / 2 - mv_i² / 2

Where v_i is speed at t = 0 and v_f is speed at time = t.

Kinetic energy is a scalar and has the same units as work (i.e. Joule).