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
John David Jackson (physicist) various observable decay correlations in allowed nuclear beta decay involving the electron's momentum, its spin, the neutrino's momentum, and the nuclear spin that provide information about parity conservation or non-conservation and time reversal conservation or not. He also published an early paper on the then recently discovered muon-catalyzed fusion of hydrogen isotopes. While at the University of Illinois (1957–1967) Jackson initially continued work on weak interactions as well as strange particle interactions at low energy with Wyld and others. On sabbatical leave at CERN in 1963–64, he collaborated with Kurt Gottfried on production and decay of unstable resonances in high-energy