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Factors - weight/drag/flexibity of role etc

The strength to bend the pole will depend on the muscles and therefore the weight of the pole

Given current equipment

I guess we are looking for an individual ability in a given tournament - the winner on the day may not reach record height, but out perform the competition.

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hmmm - i dont see why this shouldnt be improved by a lot

imagine a very flexible pole ( they bend as u plant them to take off) then the flex unwinds and "catapults" you upwards and (with your own forward runnin momentum) forwards a bit - so - theoretically with a good material for the pole maybe its possible to fling the vaulter very high - maybe NASA will start to use this technique to get things into earth orbit! :)

Edited by oozie
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I guess we are looking for an individual ability in a given tournament - the winner on the day may not reach record height, but out perform the competition.

Factors - weight/drag/flexibity of role etc

The strength to bend the pole will depend on the muscles and therefore the weight of the pole

Given current equipment

A few other factors are Arm-span, Speed, Height, and ability to jump. (Poles are rated by length and stiffness. Stiffness is related to the weight/strain that they are able to support). So even though a pole may be rated 180lbs, it could still be snapped in half by someone weighing 150lbs if they are strong and fast enough.

The speed, weight, height, strength, and jumping ability determine the maximum weight pole that a person could bend. Sergey most likely was using the maximum rated pole for his world record abilities. (He was probably about 160lbs and using a pole rated for 210lbs if I had to guess). I am using the measurement of "pounds" loosely, considering his pole was probably rated in the metric equivalent.

Assuming that the world record was performed by a man that maxed out his own human stats relating to his pole's stats... And the fact that his pole was the longest/strongest possible in relation to circumference, a considerably higher jump could not be achieved without the use of a new material.

Otherwise, the pole would most likely

1. Be too long to support the strain of a higher jump.

or

2. Be too wide/thick to have a grip strong enough to hold onto while bending the pole.

I believe that if a different material were used, it could be possible to significantly increase the record... but then again... what would you consider a significant increase?

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KE=(1/2)mv^2

m=mass

v=velocity

PE=mgh

g=gravitational acceleration around 9.8 m/s^2

h=height

Let KE=PE

(1/2)mv^2=m(9.8m/s^2)(6.14 m)

The mass cancels out so solving for v you get

v=10.97 m/s.

You would have to run faster than 10.97 m/s to jump any higher. When Michael Johnson set the world record in 2000 he averaged

a speed of 10.35 m/s. It has been estimated that he peaked at around 11.6 m/s, and he wasn't carrying a pole

It is all about energy conservation. The higher you go the higher your potential energy. When you run you gain kinetic energy. When you jump this kinetic energy is converted to potential energy. There is a limit to how fast the human body can run, and therefore how high one can jump.

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KE=(1/2)mv^2

m=mass

v=velocity

PE=mgh

g=gravitational acceleration around 9.8 m/s^2

h=height

Let KE=PE

(1/2)mv^2=m(9.8m/s^2)(6.14 m)

The mass cancels out so solving for v you get

v=10.97 m/s.

You would have to run faster than 10.97 m/s to jump any higher. When Michael Johnson set the world record in 2000 he averaged

a speed of 10.35 m/s. It has been estimated that he peaked at around 11.6 m/s, and he wasn't carrying a pole

It is all about energy conservation. The higher you go the higher your potential energy. When you run you gain kinetic energy. When you jump this kinetic energy is converted to potential energy. There is a limit to how fast the human body can run, and therefore how high one can jump.

There is another factor.

As the vaulter transforms his kinetic energy to potential energy, he raises his center of mass by an a mount v2/2g.

But he raises his center of mass an additional amount by pulling downward on the pole as it nears vertical position.

Think here of performers on still rings and high bar, who begin with no kinetic energy.

Thus the strength of the vaulter's arms comes into play as well as his top running speed.

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World record in pole vaulting is belong to Sergey Bubka as 6.14 m.

Can you prove that nobody can improve this at a considerable amount?

Theorically of course.

Given that the IAAF has no restrictions at all on:

A) the length of the pole

B) the material the pole is made from, or

C) the pole's energy storage ability

I see no way to claim that this number can't be improved on significantly. Say, a pole made from a liquid suspended solution that solidifies when an electrical charge passes through it. Vaulter approaches, plants the pole, pole starts to bend at one rate, the vaulter triggers an electrical charge in the pole, and pow...shot up into the air with an energy return much greater than the energy being put into the pole by just the vaulter's muscles and velocity.

Or, for a more mechanical version, picture a pole that *starts* already bent, with a spring-loaded mechanism the vaulter cranks before starting their run. they plant the already bent pole, which bends some more, like a usual pole, to allow them the normal beginning of an approach. Then, flick a button, release the spring-loaded energy in the pole, pole straightens at a greatly increased rate...much higher vault.

:D

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Assuming that the question is "Can you prove that nobody can improve Sergey Bubka's 6.14m record" I would yes.

Given that his record was set in the past (set in 1994 I believe), then his record is what it is and cannot be changed, except of course if time travel were possible, but even then, since Sergey retired from the sport in 2001, it's not likely that at this point in time he could improve that record even if he could travel back in time and do it over.

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in response to the post about KE=PE... this is also asuming a perfect system in which Kinetic energy becomes elastic potential energy and the kinetic energy again without any loss of energy. as well as removing all factors such as wind resistance. making the possability of anyone beating it even more unlikely. even though the the equation given is not totally correect because if i am correct, it fails to include the force of the thrust of the upper body on the pole at the time in which the sumation of all kinetic energy is transfered into potential.

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in response to the post about KE=PE... this is also asuming a perfect system in which Kinetic energy becomes elastic potential energy and the kinetic energy again without any loss of energy. as well as removing all factors such as wind resistance. making the possability of anyone beating it even more unlikely. even though the the equation given is not totally correect because if i am correct, it fails to include the force of the thrust of the upper body on the pole at the time in which the sumation of all kinetic energy is transfered into potential.

It is a theoretical approximation as any calculation would be. Even if you were to include every factor imaginable it would still be an approximation. The kinetic energy, of the runner, is going to be the most significant source of energy. The calculation also does not account for the loss of mass when the vaulter lets go of the pole. Although I guess the pole itself has also gained potential energy by moving from horizontal to vertical, raising its CG.

How much thrust could you really generate using only your arms? I am trying to imagine someone grasping a flag pole and "jumping" using only their arms. How high could you actually jump?

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It is a theoretical approximation as any calculation would be. Even if you were to include every factor imaginable it would still be an approximation. The kinetic energy, of the runner, is going to be the most significant source of energy. The calculation also does not account for the loss of mass when the vaulter lets go of the pole. Although I guess the pole itself has also gained potential energy by moving from horizontal to vertical, raising its CG.

How much thrust could you really generate using only your arms? I am trying to imagine someone grasping a flag pole and "jumping" using only their arms. How high could you actually jump?

Don't forget about the energy that the vaulter puts into the pole when he flexes his abdomen and bends his body into an acute angle (when he kicks his feet up). This adds significant downward force into the pole beyond that of his run&jump. So even though some of the potential energy is lost in the transition, a great amount of force is added even after his feet have left the ground.

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It is a theoretical approximation as any calculation would be. Even if you were to include every factor imaginable it would still be an approximation. The kinetic energy, of the runner, is going to be the most significant source of energy. The calculation also does not account for the loss of mass when the vaulter lets go of the pole. Although I guess the pole itself has also gained potential energy by moving from horizontal to vertical, raising its CG.

How much thrust could you really generate using only your arms? I am trying to imagine someone grasping a flag pole and "jumping" using only their arms. How high could you actually jump?

just saying... the thrust generated by thrust, while seemingly unsignificant is greater than you might think. the amount of energy stored in the vaulting pole is much greater because it does not rely on a single collision but a Force over time. so if say, a 75 kilo man were to thrust a flexible pole in the ground there is a good possibility that he would quite possibly lift himself off the ground. and even if he doesnt, we are not at a total loss because the force generated due to the (9.8m/s2) a and the (75kg) mass means that he couldve generated more the 700 N without moving an inch. and yes i realize that it would be impossible to calculate them all but i was just stating a few the might result in energy loss and one that probobably could compensate for the lack of velocity of the runner.

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