Mecanics/Dynamics/Motion

Gravity's Rainbow

GRAVITY’S RAINBOW launches five small balls into five rubber cups with amazing accuracy. The exhibit employs a steel raceway, whose angle can be adjusted up or down, to vary the distance each ball travels. A catch mechanism holds each ball in place alone the rail; when the catch is released all the balls are launched off the end of the rail. The balls that are the highest go out the farthest, but regardless of the speed at which it is launched, each ball falls in a parabolic arch (thus the name "Gravity's Rainbow.") If the rubber cups are set in the proper positions they catch each ball, proving that the arc of each ball is predictable. It is possible to move the launch point of each of the five balls and the position of each of the five cups. One can experiment with all elements of the exhibit: the angle of the rail, the number of balls, and the launch and landing points of the balls. A clever net assembly catches dropped balls and provides a place to keep spare balls.