The energy, measured in joules, a body possess by virtue of its motion and which is equal to work a body would do if brought to rest. A body of mass m (kilograms) with speed v (meters per sec.) has translational (or classical) kinetic energy T=1/2mv2. In contrast, a rotating body with a moment of inertia I about its axis of rotation and an angular velocity w has rotational kinetic energy T = 1/2Iw2. Kinetic energy is distinguished from potential energy (i.e., energy stored in a body such as a coiled spring due to its position, shape or state). The sum of potential and kinetic energy gives the internal (or thermodynamic) energy of a body.