The cradle is better than the track because it allows for larger weights, where the track would require a denser material or hollow particles; but the track is easier for measuring incoming and outgoing force because on a steady grade, it’s simply a measure of distance, which is easy to capture roughly, even without a camera.

If momentum = velocity*mass, then doubling the velocity will double the momentum. Using the cradle, if you drop a ball from very very close to the first stationary ball, a single ball will move from the other side and move a very very short distance. If you then drop the ball from perpendicular, a single ball will move from the other side, and rise to (nearly) perpendicular. I have seen this much in my own observations. I don't think we need to do any calculations to understand that the impact velocity in the first essay is way less than half the impact velocity in the second essay (we don’t need exact numbers; we just need to know that the impact velocity is more than double). That means we have met your criteria for increasing the momentum to more than that of two balls at the first velocity, yet one ball still comes out.

A mental model to demonstrate my theory of “two particles in = two impacts = two particles out” is to imagine a bit of sponge between the last two balls in a Newton’s cradle. Pull the second ball out (which will push the first ball ahead of it) to a great enough height that the momentum of the outside ball’s impact is enough to completely squeeze the sponge and cause a second impact wave. The second ball would impact measurably later than the first, and before the ejected particle came back. Pretty clearly, two balls will emerge from the other side. This is what I think is happening on a micro scale when two independent balls are dropped together.>> ^oritteropo:

Thanks <img class="smiley" src="http://cdn.videosift.com/cdm/emoticon/smile.gif">
I was actually going to suggest that the first part of the experiment should be fairly easy to replicate, with a track and marbles or ball bearings or similar. Unless you have a constant grade the velocity (and therefore momentum) calculations will be a bit tedious, and it occurs to me that angular momentum may have some effect too, so perhaps a video camera and some marks on the track (or sensors and a microcontroller) to directly measure the velocity just prior to impact would be easier. To confirm or disprove my assertion you want to keep increasing the momentum of impact until it's more than the momentum of a two balls, and see what happens.
There are videos of a Newton's cradle type setup only with different sized balls, I might go looking tonight.
>> ^messenger:
That shoulda been @oritteropo too.

Thanks

I was actually going to suggest that the first part of the experiment should be fairly easy to replicate, with a track and marbles or ball bearings or similar. Unless you have a constant grade the velocity (and therefore momentum) calculations will be a bit tedious, and it occurs to me that angular momentum may have some effect too, so perhaps a video camera and some marks on the track (or sensors and a microcontroller) to directly measure the velocity just prior to impact would be easier. To confirm or disprove my assertion you want to keep increasing the momentum of impact until it's more than the momentum of a two balls, and see what happens.

There are videos of a Newton's cradle type setup only with different sized balls, I might go looking tonight.

p.s. Didn't find that one, but did find a good explanation of the one vs two ball collision issue in Newton's cradle:



Based on that, I wonder if a slowmo of the ball in the original video might've shown that it bounced slightly before coming to rest?
>> ^messenger:

That shoulda been @oritteropo too.

That vocalist would fit right at home with Cradle of Filth.

This thread has gotten me very curious to try all these things out for myself.

As far as equally weighted particles go, what you describe is not what we observe. We always see the same number of particles leave as came in, no matter their total momentum. A single particle going 1m/s ejects one particle also going 1m/s (I'm talking in ideal terms). A single particle going 2m/s doesn't release two particles going 1m/s, just one going 2m/s. The same particle going 100m/s likewise doesn't release 100 particles going 1m/s, nor 50 going 2m/s nor any other combination. As the force passes through the stationary particles, there's nothing to say what the mass or velocity of the striking particle was, just what the product of those two things was.

As for different sized particles, not having seen this done, if a solid (I mean a single piece, or welded together) 2kg particle came in at 1m/s, I predict a single 1kg particle would be ejected at 2m/s. My reason is the same as above: that when one ball strikes, the only information transmitted through the stationary particles is the total amount of force, not the velocity or mass of the striking object. Thus, the force transmitted through the stationary particles would be identical whether a 1kg ball struck at 2m/s or a 2kg ball struck at 1m/s. All this force is transmitted into the last ball which leaves with the same amount of force in the form of velocity as a factor of its mass, whatever that may be.

I think fusing the two balls together would fundamentally change their behaviour. I think when two loose balls hit together, the first one hits the stationary ones, bounces back towards the second ball which then stops, sending a second shock wave through the stationary particles, thus sending two signals very close together, and releasing two particles out the other side.

To continue the thought experiment, what if it were a 1.2kg particle striking a row of 1kg balls? I think it would be one particle going out at 1.2m/s, rather than 1 particle at 1m/s and a second at 0.2m/s or two of them together at 0.6m/s.>> ^heathen:

As you said momentum is mass velocity, and force is mass acceleration.
It's the mass of the particles entering that determines the mass of the particles leaving.
As the balls in a Newton's cradle all have equal mass it's tempting to restate that as the number of particles rather than the mass of the particles.
However if you designed a cradle to have four 1kg balls and one 2kg ball then swinging the 2kg ball would cause two 1kg balls to be displaced. (The same effect as taping or gluing two 1kg balls together.)
In a normal Newton's Cradle the acceleration, due to gravity, is constant.
The constant mass and constant acceleration cause the predictability, as the only energy lost is to air resistance and other negligibles such as sound or minimal compression of the balls on impact.
The forces introduced by the magnet scale inversely with distance, making the outcome a lot more unpredictable.

>> ^messenger:

I know that multiple balls hitting one side will cause multiple balls to be released from the other side, but momentum isn't measured by counting the incoming particles; it's measured by mass velocity, and that's all. One ball hitting with great speed usually releases one ball at great speed out the other side. Two balls with very low speed, even with less total momentum than the single fast-moving ball, will release two balls from the other side at the same low speed. It's something about the number of particles, not their momentum, that determines how many are ejected.

As you said momentum is mass*velocity, and force is mass*acceleration.

It's the mass of the particles entering that determines the mass of the particles leaving.
As the balls in a Newton's cradle all have equal mass it's tempting to restate that as the number of particles rather than the mass of the particles.
However if you designed a cradle to have four 1kg balls and one 2kg ball then swinging the 2kg ball would cause two 1kg balls to be displaced. (The same effect as taping or gluing two 1kg balls together.)

In a normal Newton's Cradle the acceleration, due to gravity, is constant.
The constant mass and constant acceleration cause the predictability, as the only energy lost is to air resistance and other negligibles such as sound or minimal compression of the balls on impact.

The forces introduced by the magnet scale inversely with distance, making the outcome a lot more unpredictable.

I know that multiple balls hitting one side will cause multiple balls to be released from the other side, but momentum isn't measured by counting the incoming particles; it's measured by mass*velocity, and that's all. One ball hitting with great speed usually releases one ball at great speed out the other side. Two balls with very low speed, even with less total momentum than the single fast-moving ball, will release two balls from the other side at the same low speed. It's something about the number of particles, not their momentum, that determines how many are ejected.>> ^oritteropo:

Try splitting the beads in a Newton's cradle so there are more than one swinging in at the end, like this:
[embed removed]
It's not that the balls know anything in particular, it's that the momentum generated by a single ball is enough to dislodge an equal ball from the other end. In the case of the three balls, there is the right amount of momentum to dislodge three balls.
Now, when we have a magnet involved the single bead is accelerated towards the magnet at a great rate of knots imparting extra momentum so it's now equivalent to many balls (with just gravity) and the only thing stopping all the balls on the other side of the magnet flying off is that the same magnetic force is stopping the closer ones from moving.
>> ^messenger:
Love it, as with just about anything with Sixty Symbols.
I'd like to know why two balls broke off, rather than one, which is what happens in Newton's Cradle, no matter how hard to smack them. The row of particles has no way of knowing that the incoming particle was accelerated before it struck, so there must be something else at work here. I wonder if it's the incoming particle shifting the whole mass in the negative direction as it pulls on the magnet, and if the magnet were fixed in place if just one ball would move off.

Try splitting the beads in a Newton's cradle so there are more than one swinging in at the end, like this:


It's not that the balls know anything in particular, it's that the momentum generated by a single ball is enough to dislodge an equal ball from the other end. In the case of the three balls, there is the right amount of momentum to dislodge three balls.

Now, when we have a magnet involved the single bead is accelerated towards the magnet at a great rate of knots imparting extra momentum so it's now equivalent to many balls (with just gravity) and the only thing stopping all the balls on the other side of the magnet flying off is that the same magnetic force is stopping the closer ones from moving.
>> ^messenger:

Love it, as with just about anything with Sixty Symbols.
I'd like to know why two balls broke off, rather than one, which is what happens in Newton's Cradle, no matter how hard to smack them. The row of particles has no way of knowing that the incoming particle was accelerated before it struck, so there must be something else at work here. I wonder if it's the incoming particle shifting the whole mass in the negative direction as it pulls on the magnet, and if the magnet were fixed in place if just one ball would move off.

Love it, as with just about anything with Sixty Symbols.

I'd like to know why two balls broke off, rather than one, which is what happens in Newton's Cradle, no matter how hard to smack them. The row of particles has no way of knowing that the incoming particle was accelerated before it struck, so there must be something else at work here. I wonder if it's the incoming particle shifting the whole mass in the negative direction as it pulls on the magnet, and if the magnet were fixed in place if just one ball would move off.

Oh, Jebus! Rapture is such a bummer! I just want to get married and have kids before.
These people are so delusional, I don't think they even understand what is preached to them since cradle. They just "believe" it because someone with authority told them is true. Everyone's nodding in front of the preacher so they should do it too. No rational behind it, but would be so sad to leave this life unfulfilled ... and live up there in the clouds with jebus, that would be boring, now that's a rational.

[edit: added some further comments, because this is too juicy]
And there's the "converted has been atheist" at the beginning made me giggle as well. I don't think he ever was one and even if he ever was one, I believe he converted for the vgeegee, which in his case is a very strong argument. So they'll spawn some kids that will learn from their father to shut the fuck up if there's anything to gain. Al in all just the right thing for the future of this world.

I didn't even watched the whole thing, 12mins into it.

I kept waiting for Richard Gere [cradling Deborah Winger in his arms of course] to enter from stage left =o)

>> ^hpqp:

I wholly agree that I detest these once atheists that have literally taken what is normally a balanced "naught" position as to God(s) existence barring evidence and instead these anti-theists ditch that stance and deem that not only is all religion a wash, but any God is as well. They're very "militant" in nature and seem to draw in those that are less secure about their own opinions; kind of like the Westboro Baptists. Unfortunately, they are also very pro-active, boisterous, and vitriolic in nature--worse of all they call themselves atheists still, giving the rest of us a bad rap.
Care to give some examples?



This is from our dear atheist, Christopher Hitchins. (I was fairly sure Hitchins was like this, but i couldn't remember specific points like you said; well i found a much better source for the matter: a small letter by him over this exact matter).

Christopher Hitchins little note (this drew some fire too it looks like when it came out):

------
You seem to have guessed, from some remarks I have already made in passing, that I am not a religious believer. In order to be absolutely honest, I should not leave you with the impression that I am part of the generalized agnosticism of our culture. I'm not even an atheist so much as I am an antitheist; I not only maintain that all religions are versions of the same untruth, but I hold that the influence of churches, and the effect of religious belief, is positively harmful. Reviewing the false claims of religion I do not wish, as some sentimental agnostics affect to wish, that they were true. I do not envy believers their faith. I am relieved to think that the whole story is a sinister fairy tale; life would be miserable if what the faithful affirmed was actually the case.

Why do I say that? Well, there may be people who wish to live their lives under a cradle-to-grave divine supervision; a permanent surveillance and [around the clock] monitoring [a celestial North Korea]. But I cannot [personally] imagine anything more horrible or grotesque. It would be worse, in a way, if the supervision was benign...

I think that this conviction does bear on the mental and moral resources that are necessary if one hopes to live [on the contrary, if one hopes to live in dissent or if one hopes to live] "as if" one were free. In a much-quoted reflection on America's original sin [of slavery], Thomas Jefferson said, "I tremble for my country when I remember that god is just." However, if there really was a god and he really was just, then there would be little enough for believers to tremble about; it would be a consolation that infinitely outweighed any imaginable earthly care.

I have met many brave men and women, morally superior to myself, whose courage in adversity derives from their faith. But whenever they have chosen to speak or write about it, I find myself appalled by the instant decline of their intellectual and moral standards. They want god on their side and they believe they are doing his work - what is this, even at it's very best, but an extreme form of solipsism? [In other words "don't mind me I'm just doing god's work, I'm very modest." A poor syllogism, or a very humble humility, is defined by them.] They proceed from conclusion to evidence; our greatest resource is the mind, and the mind is not well-trained by being taught to assume what has to be proved.

This arrogance and illogic is inseparable even from the meekest and most altruistic religious affirmations. A true believer must believe that he or she is here for a purpose and is an object of real interest to a Supreme Being; he or she must also claim to have at least an inkling of what that Supreme Being desires. I have been called arrogant myself in my time, and hope to earn the title again, but to claim that I am privy to the secrets of the universe and its creator - that's beyond my conceit. I therefore have no choice but to find something suspect even in the humblest believer, let alone in the great law-givers and edict-makers of whose "flock" (and what a revealing word that is) they form a part.
------------------------
It might sound provincial and (oh dear) Eurocentric to say this, but not even those of us who had taken the gloomiest view of the arms race and the Cold War had ever expected to see a full-dress reprise, in Europe, of internment camps, the mass murder of civilians, the reinstitution of torture and rape and deportation as acts of policy. This was the sort of thing we had read about from six decades before; some of us (including myself) had met and got to know some survivors of that period. And of course, in a recess of our minds we had played the imaginary game: what would I do about the knock on the door; how would I react if the neighbors were being marched off to the station?

That tired analogy turned out to be uncomfortably useful, because when all this ghastliness did get under way again, the political class in Europe and America behaved for the most part with the same wretched combination of complacency and complicity that it had exhibited when Fascism first came to call.
------

Here is one example. I do know that there are also a few more writers out there that are self-described, some not, ant-theists. Hopefully, this is the exact kind of thing you are looking for @hpqp . I'm just not terribly sure their ferocity over this right now is the right call. But, as I point out it certainly SHOULD be expected as many people in religion have done nothing, but callously call these once only atheists the living devil, the worst people alive, plus every demonic curse that can be called upon a person. Then they went further and threatened them with bodily harm; from individual members to actual leaders amongst these communities. Your house is vandalized and disgraced, your telephones ring non-stop to the rhythm of a religious battle hymn. These are things you wouldn't expect from good natured, Christ loving, religious people. I'm sure @shinyblurry will make sure it's known that these people are not Christians (and I would agree to an extent)--the problem with using this to literally sweep the whole problem under the carpet is that there is NO lesson learned. No one is harassed by the police as they should be or the media--it becomes a living nightmare to fight these people. Soon all you have left is to move out of town. But, in Christopher Hitchins example he is simply too famous to escape this.

I used to work at a lumber yard. I could write pages of hideous things I've seen people do. Never seen this one, though. But, a guy once used twine to cradle a 22' LVL underneath his truck. Nobody saw him doing it until he drove away...I can imagine him trying to stop and having it fly out...soooooo stupid.

If you don't know what an LVL is...
http://en.wikipedia.org/wiki/Laminated_veneer_lumber

>> ^honkeytonk73:

The middle east was once a center for science and knowledge. A cradle of knowledge that we owe MUCH to. Then the fundies gained in power. Now the middle east is in the technological and social outhouse with a grim outlook indeed. The US at this point can go either way. Go fundie and return to the middle ages, or come to it's senses and realize this mythology shit isn't the path to follow if society and science wants to evolve into something better for all mankind.


the decline and current state of the middle east has little to nothing to do with religion and practically everything to do with the Golden Horde, particularly the siege of baghdad in 1258. but we gotta demonize something right? religion it is

I doubt it..want to have a bible-off? In my mind, if you truly understood the Word you never would have abandoned Him. Also, that no one can comprehend the bible without the Spirit.

I am not so thin skinned, btw..but I am conscious of having Gods name dragged through the mud..

how about we start over and see where the thread takes us?

>> ^longde:
hehe. An atheist quoting the bible is a bit like a prisoner suing the victim of his crime.
I'm not an atheist, but I certainly don't believe in Christiantiy, and I got here from being a devout christian from the cradle to high school. I dare say I know the bible better than you do, having studied it at length and daily for all those years.
It just strikes me as strange that you are put off at scorn from nonbelievers. At least you are honest, though. I'm not saying I was never wary of being made fun of when I proselytized people. But back then, it was face-to-face; while today you have an anonymous handle and avatar to hide behind.