Appalachian State University professor Jeff Goodman wanted to show his students the interaction between period and pendulum length.
Instead of a boring video or scientific graphs displayed on a white board, Goodman created a giant pendulum using 16 bowling balls.
The balls, lined evenly apart, and arranged in a perfectly straight line, were hung with even wires on a wooden frame.
When dropped at the same time, the bowling balls began shifting in an incredible and almost artful and graceful way.
Here’s Goodman explanation of the experiment:
“** What am I seeing? How does this work? ** The length of time it takes a ball to swing back and forth one time to return to its starting position is dependent on the length of the pendulum, not the mass of the ball. A longer pendulum will take longer to complete one cycle than a shorter pendulum. The lengths of the pendula in this demonstration are all different and were calculated so that in about 2:40, the balls all return to the same position at the same time – in that 2:40, the longest pendulum (in front) will oscillate (or go back and forth) 50 times, the next will oscillate 51 times, and on to the last of the 16 pendula which will oscillate 65 times. Try counting how many times the ball in front swings back and forth in the time it takes the balls to line up again, and then count how many times the ball in back swings back and forth in the same time (though it’s much harder to keep your eye on the ball in back!)”
