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Bike vs Train?

SilverSliver said:
Dude... Ever heard of an elastic collision? Look it up and edumacate yourself. I made the approximation (admittedly poor, given the severe weight differences) that the motorcycle's final velocity was negligible, but I wasn't taking things all that seriously. If you want to work it out "properly", go right ahead. After four times the work, you might find that I was a couple orders of magnitude off, but who really cares? Any number you come up will be so far from a "real world" answer so as to be completely meaningless - but if it keeps your panties untwisted, go for it. :party
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Don't lecture me on edumacation when you're trying to do bullshit like "conserve kinetic energy" which doesn't happen.
 
Kestrel said:
The Large Hadron Collider - the particle accelerator that you might have recently heard about in Switzerland - gives us individual protons colliding with one another at speeds so high that they have the energy of freight trains slamming into one another.
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Bullshit.
 
Aulicious - doesn't momentum increase exponentially with velocity compared to mass? i'm not edumacated or else I'd figure it own on my own. But wouldn't the energy potential to create anti-matter(one goal of the LHC) be far greater than 2 trains crashing into eachother?
 
Lights_Guy3 said:
That was spectacularly unimpressive.

I wanted to see CARNAGE!!!!
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Oh... it's carnage you want?

well why didn't you say so!?!?

[youtube]__Dw3KiauKA[/youtube]
[youtube]o1jiI47KAnI[/youtube]
[youtube]c8goK-FWlmI[/youtube]
[youtube]PIsCzneQqi0[/youtube]
[youtube]9u9Vl2tPJaQ[/youtube]
[youtube]QfFCC71vhDM[/youtube]
 
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Hellfish_Monkey said:
Oh... it's carnage you want?

well why didn't you say so!?!?

[youtube]__Dw3KiauKA[/youtube]
[youtube]Dmh6Ra515vU[/youtube]
[youtube]c8goK-FWlmI[/youtube]
[youtube]PIsCzneQqi0[/youtube]
[youtube]9u9Vl2tPJaQ[/youtube]
[youtube]QfFCC71vhDM[/youtube]
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:thumbup:thumbup:thumbup:thumbup
 
Var said:
Aulicious - doesn't momentum increase exponentially with velocity compared to mass? i'm not edumacated or else I'd figure it own on my own. But wouldn't the energy potential to create anti-matter(one goal of the LHC) be far greater than 2 trains crashing into eachother?
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Momentum is mass times velocity. Kinetic energy and momentum are different. Calculating how much a bike will move a train in a collision is a momentum problem, not an energy problem.

The energy of two particles colliding in the LHC is vastly less than that of 2 trains crashing. The particles are going very fast but a train weighs ridiculously more than a proton. The highest energy particles from space that have ever been measured had the kinetic energy of a baseball, and the LHC produces particle energies many magnitudes of order less than that.

Think of it this way...a single proton in the LHC has far more energy than a single proton in a train, but the train collision has more energy overall because it has way more protons in total.
 
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Aluisious said:
Don't lecture me on edumacation when you're trying to do bullshit like "conserve kinetic energy" which doesn't happen.
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Actually, it does. Most collisions fall between the boundaries of being either completely elastic or inelastic; I chose the former as being convenient. You can't use your precious conservation of momentum (except in either of those limiting cases) because post-collision you don't know what percentages of the masses are going forward or backward or the velocities at which they are doing it. Thanks for playing, have a nice day.



@Hellfish_Monkey: :laughing Yeah, well, my finger's a bird and your face is invalid. :twofinger :p
 
the real question is how much high explosive do you have to load on the motorcycle to get the train to derail.
 
Aluisious said:
The energy of two particles colliding in the LHC is vastly less than that of 2 trains crashing. The particles are going very fast but a train weighs ridiculously more than a proton. The highest energy particles from space that have ever been measured had the kinetic energy of a baseball, and the LHC produces particle energies many magnitudes of order less than that.
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Really? Apparently the BBC article lied and made it sound cooler than it really was. Just a baseball bat? I was under the impression that they were moving so god damned fast that there was a metric shit ton of energy behind them. That's a bit of a let down.

Oh well. LHC may not have been as cool as I believed it to be, but at least we've still got motorcycles. That's something to be happy about.
 
So I read that the bigger ions at full speed will have an energy of just over 1100 TeV. As a contrast point , 1 TeV is the same energy a mosquito has in flight.

It makes the LHC seem a lot less scary like kestrel said
 
Kestrel said:
Really? Apparently the BBC article lied and made it sound cooler than it really was. Just a baseball bat? I was under the impression that they were moving so god damned fast that there was a metric shit ton of energy behind them. That's a bit of a let down.

Oh well. LHC may not have been as cool as I believed it to be, but at least we've still got motorcycles. That's something to be happy about.
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In experiments, researchers found that an 86-microsecond exposure of the beam would bore a hole 40 meters into a block of copper.

That's still pretty badass. :laughing
 
SilverSliver said:
Actually, it does. Most collisions fall between the boundaries of being either completely elastic or inelastic; I chose the former as being convenient. You can't use your precious conservation of momentum (except in either of those limiting cases) because post-collision you don't know what percentages of the masses are going forward or backward or the velocities at which they are doing it.
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If you crash a bike into the side of a train, you can be pretty sure the bike is going to crumple and you can treat the train and bike as one object to calculate the final momentum. That is a much more realistic scenario than a perfectly elastic collision between a bike and a train.

http://hyperphysics.phy-astr.gsu.edu/Hbase/elacol.html

A perfectly elastic collision is defined as one in which there is no loss of kinetic energy in the collision. An inelastic collision is one in which part of the kinetic energy is changed to some other form of energy in the collision. Any macroscopic collision between objects will convert some of the kinetic energy into internal energy and other forms of energy, so no large scale impacts are perfectly elastic. Momentum is conserved in inelastic collisions, but one cannot track the kinetic energy through the collision since some of it is converted to other forms of energy.
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SilverSliver said:
Thanks for playing, have a nice day.
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:rolleyes Not quite.
 
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