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
Office of Energy Efficiency and Renewable Energy its changing scope, including the Office of Conservation and Solar Applications (CSA), the Office of Conservation and Solar Energy (CSE), and the Office of Conservation and Renewable Energy (CRE). The agency gained its current name, the Office of Energy Efficiency and Renewable Energy, in 1993. The EERE's mission is defined as "to create and sustain American leadership in the transition to a global clean energy economy." The office also develops initiatives to advance specific technologies. The Office of EERE is led by the Assistant Secretary of Energy Efficiency and Renewable Energy, who is appointed by the president and confirmed by