Newton's cradle Newton's cradle Newton’s cradle is a device that demonstrates conservation of momentum and energy using a series of swinging spheres. When one sphere at the end is lifted and released, it strikes the stationary spheres, transmitting a force through the stationary spheres that pushes the last sphere upward. The last sphere swings back and strikes the still nearly stationary spheres, repeating the effect in the opposite direction. The device is named after 17th-century English scientist Sir Isaac Newton. It is also known as Newton's balls or Executive Ball Clicker. A typical Newton's cradle consists of a series of identically sized
Conservation of energy not escape the attention of Gottfried Wilhelm Leibniz. It was Leibniz during 1676–1689 who first attempted a mathematical formulation of the kind of energy which is connected with "motion" (kinetic energy). Using Huygens' work on collision, Leibniz noticed that in many mechanical systems (of several masses, "m" each with velocity "v"), was conserved so long as the masses did not interact. He called this quantity the "vis viva" or "living force" of the system. The principle represents an accurate statement of the approximate conservation of kinetic energy in situations where there is no friction. Many physicists at that time, such