 Finally, in Newtonian mechanics, an object in motion relative to a reference frame also has kinetic energy, or energy of motion. Kinetic energy, like all forms of energy, can be transformed into another kind of energy. So, for example, one could measure the kinetic energy of a moving billiard ball by having it collide with a ball of soft putty or a spring that brings the ball to rest and measuring the energy absorbed by the putty or spring. There is no single standard symbol for kinetic energy, though most elementary physics textbooks use \(KE\), more advanced books tend to use \(T\). 