Bike vs Train?

[Aluisious]

WTF, is that real?

That would ruin your day for sure.

 

[PunkRockMonkey]

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.

So... wait... what you're saying is that you'd have to use a mini-bike to derail the train?

Here we have what looks to be an early attempt by a rider on a bicycle... they fail on the execution, though.

[youtube]Wl_0XUR1BCg[/youtube]

 

[Valgar]

View attachment 277271

NEEDS MOAR GOATSE HANDS

 

[Carlo]

This is purely hypothetical.

My friend and I are arguing about whether or not a motorcycle could derail a train simply from impact.

So let’s speculate... How fast would the bike have to go? I already understand that the speed required is not going to be a speed that the bike can actually attain, but it’s just for fun anyways...

Situation:

Train going 50mph. 400lb motorcycle with 200lb rider hits the engine perpendicular.

Would the rider aim for the trucks?

Any guesses?

Well, since the kinetic energy of a moving object increases as the square of velocity (just like Einstein's formula E=MC sqaured), at some speed, anything could derail a train, provided enough of the energy available can be transferred to the train. Aiming for the trucks would provide the most effective energy transfer, because not only are they ver solid objects that won't deform significantly, they're also the place that would provide the most effect towards derailing the train.
The rider's weight probably won't have much influence on the outcome, because he'd be ground into hamburger before transferring much energy to the train, but the energy of the heavy parts of the bike would be transferred to the train reasonably well.

 

[SilverSliver]

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.

Which would be a perfectly inelastic collision. I already said that I chose the other boundary, that of a perfectly elastic one, because it was convenient (in that it reduced to a single equation with the approximation that the bike's post-collision velocity was negligible.) As far as realism goes, there's so much more to consider beyond the actual collision momentum/energy transfer as to make this whole 'debate' more than a little silly. Kudos for the linkage, though.

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.

You're talking about different things. Everyone else is talking about individual proton energy, you're talking about total beam energy. At peak luminosity (i.e. with as many protons they can stuff in there) an individual beam's energy is expected to be >350MJ. Smash two of those together, and you've got way more energy than a baseball bat.

 

[DataDan]

Enough theory. Let's see how our boys are doing against the choo-choo train menace in the real world.

Motorcyclist hits locomotive
New Holland, PA, June 2008. A motorcyclist was injured when he hit a freight locomotive at a railroad crossing without a gate or warning lights. The rider was headed south, and two locomotives not pulling cars entered the crossing from the west. He braked at the last minute, flew off the bike, and hit the lead engine.

No damage to the engine was reported.


Man killed in motorcycle-train collision
Toledo, OH, July 2008. A motorcyclist was cut in half and dragged after he crashed through a crossing gate and hit the caboose of a freight train. Because he was westbound in early evening hours, police speculate that he was blinded by the setting sun.

No damage to the caboose was reported.


Motorcyclist dies trying to beat train at crossing
Shreveport, LA, August 2008. A motorcyclist trying to beat a slow-moving train through a crossing apparently didn't see a lowered gate at the crossing. He was knocked off the motorcycle when he hit the gate and died from his injuries.

No damage to the crossing gate was reported. The train wasn't involved in the collision.​

 

[Aluisious]

The rider's weight probably won't have much influence on the outcome, because he'd be ground into hamburger before transferring much energy to the train

The rider being ground into hamburger IS "transferring" energy to the train. The train is doing the grinding, right?

"Energy transfer" is just going to make the train warmer, for the most part. You don't derail a train by making it warm. You derail it by knocking it over with momentum. Or by deforming the wheel as you say, but that's hard to do.

 

[Lights_Guy3]

Enough theory. Let's see how our boys are doing against the choo-choo train menace in the real world.

Motorcyclist hits locomotive
New Holland, PA, June 2008. A motorcyclist was injured when he hit a freight locomotive at a railroad crossing without a gate or warning lights. The rider was headed south, and two locomotives not pulling cars entered the crossing from the west. He braked at the last minute, flew off the bike, and hit the lead engine.

No damage to the engine was reported.


Man killed in motorcycle-train collision
Toledo, OH, July 2008. A motorcyclist was cut in half and dragged after he crashed through a crossing gate and hit the caboose of a freight train. Because he was westbound in early evening hours, police speculate that he was blinded by the setting sun.

No damage to the caboose was reported.


Motorcyclist dies trying to beat train at crossing
Shreveport, LA, August 2008. A motorcyclist trying to beat a slow-moving train through a crossing apparently didn't see a lowered gate at the crossing. He was knocked off the motorcycle when he hit the gate and died from his injuries.

No damage to the crossing gate was reported. The train wasn't involved in the collision.​

Data Dan, you're awesome!!!!

 

[Aluisious]

If I'm ever somewhere on a bike and DataDan shows with a notepad or other recording device, I'm turning the bike off and getting away from it.

 

[SilverSliver]

The rider being ground into hamburger IS "transferring" energy to the train. The train is doing the grinding, right?

"Energy transfer" is just going to make the train warmer, for the most part. You don't derail a train by making it warm. You derail it by knocking it over with momentum. Or by deforming the wheel as you say, but that's hard to do.

In the interest of continued dreary and irrelevant pedantry, I should point out that if you give something momentum, you give it kinetic energy - a momentum transference is also an energy transference.


( )

 

[Lights_Guy3]

If I'm ever somewhere on a bike and DataDan shows with a notepad or other recording device, I'm turning the bike off and getting away from it.

But what if that is exactly what he was expecting you to do and it ends up that he is gathering data on motorcyclists being fucked up while NOT riding.........

 

[Sane_Man]

But what about:

A connection with everything
The building blocks of the standard
Figure 1: A periodic table of the standard model.
model and gravity are _elds over a
four dimensional base manifold. The
electroweak and strong gauge _elds
are described by Lie algebra valued
connection 1-forms,
W 2 su(2) B 2 u(1) g 2 su(3)
while the gravitational _elds are described
by the spin connection,
! 2 so(3; 1) = Cl2(3; 1)
a Cli_ord bivector valued 1-form, and
the frame, e 2 Cl1(3; 1), a Cli_ord
vector valued 1-form. The frame may
be combined with a multiplet of Higgs scalar _elds, _, to interact with the electroweak
gauge _elds and fermions to give them masses. The fermions are represented as Grassmann
valued spinor _elds, f: _ e; :e; : u; : : :g, with the spin connection and gauge _elds acting
on them in fundamental representations. The electroweak W acts on doublets of left chiral
fermions, f[: _ eL; : eL]; : : :g; the strong g acts on triplets of red, green, and blue colored
quarks, f[: ur; : ug; : ub]; : : :g; and the electroweak B acts on all with an interesting pattern of
hypercharges. The left and right chiral parts of the gravitational spin connection, !, act on
the frame and on the left and right chiral fermions. This structure, depicted in Figure 1, is
repeated over three generations of fermions with di_erent masses.
This diverse collection of _elds in various algebras and representations is, inarguably, a
mess. It is di_cult at _rst to believe they can be uni_ed as aspects of a unique mathematical
structure | but they can. The gauge _elds are known to combine naturally as the connection
{ 2 {
of a grand uni_ed theory with a larger Lie group, and we continue with uni_cation in this
spirit. The spin connection, frame, and Higgs may be viewed as Lie algebra elements and
included as parts of a \graviweak" connection. Relying on the algebraic structure of the
exceptional Lie groups, the fermions may also be recast as Lie algebra elements and included
naturally as parts of a BRST extended connection.[2, 3] The result of this program is a single
principal bundle connection with everything,
: A
= 1
2! + 1
4e_ + B +W + g +
+ _ e + : e + : u + : d) + __ + : _ + : c + : s) + __ + : _ + : t + : b)
(1.1)
In this connection the bosonic _elds, such as the strong g = dxig A
i TA, are Lie algebra valued 1-
forms, and the fermionic _elds, such as : u = : uATA, are Lie algebra valued Grassmann numbers.
(These Grassmann _elds may be considered ghosts of former gauge _elds, or accepted a priori
as parts of this superconnection.)
The dynamics are described by the curvature,
=_
F = d : A + 1
2 [ : A; : A] (1.2)
with interactions between particles given by their Lie bracket. For example, the interaction
between two quarks and a gluon is speci_ed by the Lie bracket between their generators, with
a corresponding Feynman vertex?

 

[Var]

wtf you say about my mama?

 

[Valgar]

But what about:

A connection with everything
The building blocks of the standard
Figure 1: A periodic table of the standard model.
model and gravity are _elds over a
four dimensional base manifold. The
electroweak and strong gauge _elds
are described by Lie algebra valued
connection 1-forms,
W 2 su(2) B 2 u(1) g 2 su(3)
while the gravitational _elds are described
by the spin connection,
! 2 so(3; 1) = Cl2(3; 1)
a Cli_ord bivector valued 1-form, and
the frame, e 2 Cl1(3; 1), a Cli_ord
vector valued 1-form. The frame may
be combined with a multiplet of Higgs scalar _elds, _, to interact with the electroweak
gauge _elds and fermions to give them masses. The fermions are represented as Grassmann
valued spinor _elds, f: _ e; :e; : u; : : :g, with the spin connection and gauge _elds acting
on them in fundamental representations. The electroweak W acts on doublets of left chiral
fermions, f[: _ eL; : eL]; : : :g; the strong g acts on triplets of red, green, and blue colored
quarks, f[: ur; : ug; : ub]; : : :g; and the electroweak B acts on all with an interesting pattern of
hypercharges. The left and right chiral parts of the gravitational spin connection, !, act on
the frame and on the left and right chiral fermions. This structure, depicted in Figure 1, is
repeated over three generations of fermions with di_erent masses.
This diverse collection of _elds in various algebras and representations is, inarguably, a
mess. It is di_cult at _rst to believe they can be uni_ed as aspects of a unique mathematical
structure | but they can. The gauge _elds are known to combine naturally as the connection
{ 2 {
of a grand uni_ed theory with a larger Lie group, and we continue with uni_cation in this
spirit. The spin connection, frame, and Higgs may be viewed as Lie algebra elements and
included as parts of a \graviweak" connection. Relying on the algebraic structure of the
exceptional Lie groups, the fermions may also be recast as Lie algebra elements and included
naturally as parts of a BRST extended connection.[2, 3] The result of this program is a single
principal bundle connection with everything,
: A
= 1
2! + 1
4e_ + B +W + g +
+ _ e + : e + : u + : d) + __ + : _ + : c + : s) + __ + : _ + : t + : b)
(1.1)
In this connection the bosonic _elds, such as the strong g = dxig A
i TA, are Lie algebra valued 1-
forms, and the fermionic _elds, such as : u = : uATA, are Lie algebra valued Grassmann numbers.
(These Grassmann _elds may be considered ghosts of former gauge _elds, or accepted a priori
as parts of this superconnection.)
The dynamics are described by the curvature,
=_
F = d : A + 1
2 [ : A; : A] (1.2)
with interactions between particles given by their Lie bracket. For example, the interaction
between two quarks and a gluon is speci_ed by the Lie bracket between their generators, with
a corresponding Feynman vertex?

That is possibly the worst cut and paste I've seen.

 

[SilverSliver]

But what about:

_ = fi

That particular Lie algebra is clearly isomorphic to that proposed by Pedrosa et al., which fails to account for the zero-point particle spin of magnetic monopoles in conservational eigenstates (as proven by the Valentino Conjecture.)

 

[jessaca]

A empty box car weighs approx 35 tons, and loaded one about 115 tons.

A train would more likely derail if the bike was left on the tracks. There is only about a quarter size amount of room that the wheel and the track touch.

As for trying to derail a train by running into the side of it. LOL They would just call the fire dept to hose you off, and a tow truck to pick up the bike.

 

[Menke]

Dammit, almost 80 posts and no mention of the train being on a treadmill?


Apparently the new flava of BARF is talking all about the large hardon collider.

 

[Z3n]

And the diameter of the hole would be?

Now, I'm no internettrons physisicsts, but I'm pretty sure you could feed it through a prizm, and use it's rainbow-y goodness to defend the entire US from missiles.

 

[Sane_Man]

I'm starting to see these kamikaze motorcycles, as threats, so a good defense is called for.

Imperial Forces that can deal with sub-light vehicles.

 

[Aluisious]

Uh, that train has an ATAT growing out of it.

The Photochop is weak with this one.