Tuesday, June 19, 2012

Tuesday Teaching {Tightrope Walker}

Project: Tightrope walker 

Concept: Center of Balance


I was excited to find a couple emails last week from family wanting to know the science behind some interesting phenomenons. Which inspired me to think of how much more fun this would be for your kids if they were experimenting with their very own questions. So find out your kid's questions and let me know through the 'Ask Mrs. V' button on the sidebar ---------------------->
Thanks all!

One of the questions last week was:
Why do tightrope walkers carry those long poles?

This question may or may not have been spurred on by the recent feat of Nik Wallenda crossing the Niagara Falls. I only found out about this yesterday, but after reading how many viewers this attracted, I'm sure I'm the only one to not know about this.

Source here
He crossed the Niagara Falls in less than an hour. And yes, he did carry one of those long poles. But why?

This relates to center of gravity. Remember when we made the Balancing Bird? The bird would not balance because the center of gravity was not directly over the fingertip, or balance point. We needed to adjust the 'weight' of the bird so that the center of the 'weight' was at a point directly above the fingertip. 

A tightrope walker changes his center of mass by adding a pole. 

Stand up with your feet together and have someone gently (gently, brothers! :) try to push you over. It's pretty easy, right? 
Now stand with your feet spread apart and have someone gently try to push you over. That is harder to do. Even if you were to push harder than before, you would probably not be able to push them over. 

When you are standing straight up, your center of gravity, or middle of the 'weight', is more or less your stomach. When your feet are spread apart, your center of gravity is lower than it was before. When your center of gravity is lower, you are more stable because you are closer to the balancing point.

A tightrope walker on a thin wire is not able to spread his feet apart, but they CAN lower their center of gravity by holding a drooping pole with a little weight on either end.

Find a thin sidewalk to set up your own tightrope walk and grab a broom (with the end off) to test your skills!

Also, check out this balancing experiment for your project today:

No comments:

Post a Comment