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Circus by Alex, Sarah and Sasha

We're students at Circus Juventas, a circus arts school in St. Paul, Minnesota. I guess you could say that our lives really ARE a three-ring circus! One of our hardest performances is the tightrope. Sometimes we carry a balancing pole. Sometimes we use no pole at all. Our question is: How does a pole help you balance on the high wire and how long does that pole have to be?

What did we do?
We grabbed three poles of three different lengths: 10 feet, 15 feet and 20 feet. All of them were the same weight. We built a "wobble-o-meter," which buzzes each time we lose our balance. We each strapped on the wobble-o-meter and walked the wire with no pole, the 10-foot pole, 15-foot pole and 20-foot pole. We kept track of all the buzzes. When we were done, we averaged the number of wobbles.

What did we find out?
Our results showed that the long pole helped us balance best. We think this is because the long pole doesn't rotate easily. It helps keep us steady. You know how you stick out your arms to balance while walking on a curb or balance beam? Holding a pole is like having super-long arms that help keep you up!

What can you do?
  • Walk on a curb or across a low balance beam with your eyes focused on your feet. Now look forward. Even try it with your eyes shut (have a friend or parent spot you). How does your balance differ? Why? Record what you found out. Where's the best place to focus your eyes to keep your balance?
  • Check out how the center of gravity determines whether things tip or balance. Get a ruler, a rubber band and a hammer. Put the hammer through the rubber band at about the 2-inch mark. Put the hammer handle through the rubber band too, with the handle near the 11-inch mark, on the underside of the ruler. Rest the ruler on the edge of a table top with the hammerhead hanging under the table. Why doesn't it fall
  • Use this circus investigation as a science fair project idea for your elementary or middle school science fair! Then tell us about it!
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