Why does a tightrope walker use a long pole

Imagine yourself 20 meters 66 feet above the ground on a platform, as thousands of faces watch and wait for you to style. Welcome to the world of high wire. High wire's roots are as old as ancient Egypt and first century China, where the art of "rope dancing" was performed over knives. In the s, Jean Francois Gravelet received world acclaim for cooking and eating an omelette complete with stove and neatly set table on a high wire stretched over Niagara Falls. Three different types of funambulism have evolved.

Slack wire, where the rope or wire hangs a bit loose, is popular for juggling, clowning, and sword fights. Sloped wires are attached to the ground at one end and to a pole at the other, creating an angle of about 40 degrees. The most popular of all is the high-wire act, where a taut, springy wire is used to launch dizzying acrobatic tricks and phenomenal feats of balancing. One way to view the high-wire act is to see the wire as an axis and the center of mass of the performer as having the potential to rotate about the axis.

If the center of mass is not directly above the wire, gravity will cause the performer to begin to rotate about the wire. If this is not corrected, the performer will fall. The artist often carries a balancing pole that may be as long as 12 meters 39 feet and weighs up to 14 kilograms 31 pounds. This pole increases the rotational inertia of the artist, which allows more time to move his or her center of mass back to the desired position directly over the wire.

This effect can be magnified by making the pole as long as possible and by weighting its ends. The pole also helps balance the funambulist by lowering the center of gravity.

No doubt, the entirety of walking a tightrope is centered around balance and the moment of inertia. This is the reason that tightrope walkers carry a very long pole. The pole places greater distance of mass from the rope resulting in an increase in the moment of inertia.

This, in turn, increases the period of oscillation which is the repetitive variation in a measure. This all allows for any wobbles or disruption to the equilibrium to occur slowly, giving the walker time to respond and restore equilibrium. The conditions of the rope and position of the walker must also be taken into consideration.

The rope cannot be too loose allowing for lots of swinging and movement, but it also must not be too tight, creating more vibrations. This reduces angular acceleration The result is less tipping. In addition the performer can also correct sway by rotating the pole. If he carried same rod wit same inertia , but in a higher position , he would be even less stable than he would be with no rod at all, and he would easily fall down.

But tightrope walkers don't walk like that. Making charitable guesses about mass of the balance bar, the walker in your first photo has moved his center of mass from his navel to his thigh. Next time you are trying to balance on a curb or playground balance beam or whatever, you'll notice that you're more stable with your arms stuck out than with them at your sides.

But you lifting your arms raises your center of mass, contrary to the model you present here. The purpose of a rod is to lower CoM and, secondly, to spread the mass. The second picture is just an exaggeration of the first and shows that lowering CoM, pushed to the limits can work wonders, which large inertia can't do.

I hope you eventually got it! Now, try balancing a broomstick on end on your hand. Which is easier? The broomstick is much easier because you need a much slower reaction time to do it. The importance of reaction time for the tightrope walker works exactly the same way. Show 3 more comments. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name.

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