Pistorius Fans - and Physics Fans

[DTLarca]

Blades are springs. Like trampolines are essentially springs. The force needed to deform a spring is:

F = -kx where k is the spring constant and x is the distance the spring is deformed.

The work energy is calculated:

W = -kx²

This means that for a blade twice as long a person can store 4 times as much energy - that's the x² bit of the formula. So longer bladed runner's start-off very slow, as they charge the blades with energy, just like the first jump on a trampoline is pathetic, but, like on a trampoline, eventually they get increasingly easier leaps which can also be quicker if the runner is moving mostly horizontal.

Once you have achieved a certain height on a trampoline you no longer need to jump so hard - just a little push is need each time only to overcome the efficiency losses occurring in the springs which store the energy of your jump for you while you change direction from downward to back upward.

Oscar's blades were "clipped" to ensure he did not have this advantage. Alan's blades are maybe 50% longer giving about 2.25 times as much energy conservation between strides. Alan will necessarily start off slower but once Alan hits his desired top speed all he has left to do is move his legs as fast as is practicably possible.

Pistorius does not think Alan's blades were illegal - he was just pointing out that they are undoubtedly unfair.

Basic high school mechanics - projectiles and parabolic curves - the effortless horizontal travel can be seen in this video: http://youtu.be/w-rpcIQtFrw

Video of the race starts at 2:58: http://www.youtube.com/watch?v=A9Wlp1sTnoY

Thanks

[r.bartlett]

I thought you said it was all in the past and had moved on..

lets assume you were drunk when you posted but none the less you look rather silly with all this now

Straighten up and fly right.

[slingblade]

I thought you said it was all in the past and had moved on..

lets assume you were drunk when you posted but none the less you look rather silly with all this now

Straighten up and fly right.

Richard, I am now as sick and tired of you as i am of Marc. Webram bin both of them. Enough is enough.

[r.bartlett]

Richard, I am now as sick and tired of you as i am of Marc. Webram bin both of them. Enough is enough.

Stop running to Webram like a 2 year old. Put me on ignore or grow up

[chillerman2006]

A members knowledge, mental abillity & current stabillity are shown in their posts !

Those of us that wish to learn & are always looking to move to the next level appreciate your posts Marc

Hopefully we will see alot more of you this year

Richard your own & Marc's contribution here is very much valued to me and many of the regular members, maybe its time to bin those that ownly grace us with their presence once a year to throw insults unless they can learn to move on !

A belated happy new year mate and I will find time this year to pop in for that coffee

[install monkey]

http://en.wikipedia.org/wiki/Mechani...running_blades courtesty of Wikipedia- blade technology

[r.bartlett]

A members knowledge, mental abillity & current stabillity are shown in their posts !

Those of us that wish to learn & are always looking to move to the next level appreciate your posts Marc

Hopefully we will see alot more of you this year

Richard your own & Marc's contribution here is very much valued to me and many of the regular members, maybe its time to bin those that ownly grace us with their presence once a year to throw insults unless they can learn to move on !

A belated happy new year mate and I will find time this year to pop in for that coffee

Always free for coffee and stuff :-)

ironically I actually like Sling and as he said he had put it all behind him back in 09 I thought peace had broken out..He must have searched for his posts so he could be offended by it...I really can't see what he hoped to gain by this....

[r.bartlett]

http://en.wikipedia.org/wiki/Mechani...running_blades courtesty of Wikipedia- blade technology

I don't agree he should have been allowed to run in both olympics. He's either disabled or fully abled you cannot be both at the same time.

[install monkey]

they should run on their stumps!, anytime carbon fibre technology gets into sports it becomes like F1 the length of the blades,the rigidness/springiness(technical term) the mass of the runner,the length of his thigh, can affect the race.

[hookster]

Usain Bolt is actually powered by a Ferrari engine with KERS (Kinetic energy recovery System)! He is using such incredible joint rotation speed, they had to pump liquid gallium through a Peltier cooler to control the dissipated heat energy! The high advances in TIM (Thermal interface material) was required in the design to give higher thermal conductivity!

[install monkey]

is that why my broadband /TiVo subscription is expensive-

Usain Bolt is actually powered by a Ferrari engine with KERS (Kinetic energy recovery System)! He is using such incredible joint rotation speed, they had to pump liquid gallium through a Peltier cooler to control the dissipated heat energy! The high advances in TIM (Thermal interface material) was required in the design to give higher thermal conductivity!

[r.bartlett]

Usain Bolt is actually powered by a Ferrari engine with KERS (Kinetic energy recovery System)! He is using such incredible joint rotation speed, they had to pump liquid gallium through a Peltier cooler to control the dissipated heat energy! The high advances in TIM (Thermal interface material) was required in the design to give higher thermal conductivity!

There are strong rumours he went to the lance Armstrong school of performance enhancing...

[hookster]

is that why my broadband /TiVo subscription is expensive-

Dear Mr Install we have examined you TiVo bill and would like you to point you towards your last few purchases in the TV X/Red Hot channels section.

[chillerman2006]

Dear Mr Install we have examined you TiVo bill and would like you to point you towards your last few purchases in the TV X/Red Hot channels section.

Haha

you know him tooo well , hookster

[slingblade]

Always free for coffee and stuff :-)

ironically I actually like Sling and as he said he had put it all behind him back in 09 I thought peace had broken out..He must have searched for his posts so he could be offended by it...I really can't see what he hoped to gain by this....

I love you too Richard. Yes in 2009 peace broke out when Marc left. However in 2013 he is back. I have been promised many things by moderators to no avail. Peace was accepted on my behalf on the agreement he did not come back. Marc himself agreed to delete all his posts and never darken this forum again. Why is he back?
I will not share this forum with his input, which is why i have not posted since his return other than to tell him to F off.

[monkey spanners]

http://www.youtube.com/watch?v=QAzESJ62irI

This town ain't big enough...
Jon

[Goober]

http://www.youtube.com/watch?v=QAzESJ62irI

This town ain't big enough...
Jon

F*cking Hell.....someone showing their age. Don't you just love them 70's rockers. Vaguely familiar?