Newton's Cradle as a timeless classic. The ball impact pendulum is not only a classic decorative object for the office or desk, but also provides interesting insights into physics and the law of conservation of momentum. Simply lift one or more of the outer balls and let them collide with the stationary balls – on the opposite side, the same number of balls will be set in motion. Looking for a suitable gift for curious adults and little explorers? Then the ball game is a great idea.