[Eromaveabeara]

While the symmetry is satisfying, why does the initial ball (or balls) not bounce back instead of imparting nearly all the momentum and energy to the last ball (or balls)?

The simple equations used for the conservation of kinetic energy and conservation of momentum can show this is a possible solution, but they cannot be used to predict the final velocities when there are three or more balls in a cradle, because they provide only two equations to find the three or more unknowns (velocities of the balls). They give an infinite number of possible solutions if the system of balls is not examined in more detail.
http://en.wikipedia.org/wiki/Newton%27s_cradle Nice.... infinite complexity

[smazibummigue]

Nice.... infinite complexity Until the sustem is examined in more detail, when there is one solution again.

[Eromaveabeara]

IMO, such a simple demonstration and yet science knows so little of its physics.

[Clilmence]

IMO, such a simple demonstration and yet science knows so little of its physics.

Ref?

[Piemonedmow]

Ref?

Come on Mr. D, you know better than that...

[Arr34ston]

As of 2012-10-12T11:06, "IMO" is no longer a valid signal on this forum for content that is to be taken seriously.


See: http://www.abcforums.com/showthread.php?3106

[Anatolii]

he lives in hope even if he is doomed to die in despair.

[Bgfbukpf]

he lives in hope even if he is doomed to die in despair.

I'll let you opposing nuts argue it out...LOL!

nighty night...

[Arr34ston]

// Ref?

W4

[smazibummigue]

IMO, such a simple demonstration and yet science knows so little of its physics.

What aspects of the physics are you saying that science knows little of?

[Clilmence]

What aspects of the physics are you saying that science knows little of?

I think he's talking about conservation of momentum, Rev. Dead-set complicated, that one

[smazibummigue]

I think he's talking about conservation of momentum, Rev. Dead-set complicated, that one

Well it's true that the motion of the balls can't be analysed from consideration of conservation of momentum alone, but I presume he is aware that there are other laws of dynamics.

[Clilmence]

Well it's true that the motion of the balls can't be analysed from consideration of conservation of momentum alone, but I presume he is aware that there are other laws of dynamics.

Sorry, Rev, I was just being sarky. (Reacting badly to woo at the moment. I'll be better after my IgG fix on Thursday.)

I know that the simple solution gives a small error (2%, from memory), but the whole thing is far from insoluble. Plenty of good explanations on the interwebthingy.

[smazibummigue]

So Zarkov, are you going to tell us what aspects of the physics you are saying that science knows little of?

[Arr34ston]

/* While the symmetry is satisfying, why does the initial ball (or balls) not bounce back instead of imparting nearly all the momentum and energy to the last ball (or balls)? */

I'm not convinced it occurs for a purpose, but then what if there is a barrier behind the last ball, does not the initial ball bounce back?

[Eromaveabeara]

Newton's cradle is a rather interesting device/demonstration

I like the big cover-all words... its just conservation of momentum, LOL
double speak

eg Why does two follow through..2 in 2 out.... easy LOL
and what of three ?...

I am not professing on this one.... I am in awe of Newton.

[Clilmence]

/* While the symmetry is satisfying, why does the initial ball (or balls) not bounce back instead of imparting nearly all the momentum and energy to the last ball (or balls)? */

That would make billiards a very boring game.

[Arr34ston]

// That would make billiards a very boring game.

Good point -- 'u see, if the other balls are next to a barrier, then it may well be that the initial ball bounces back, I won't claim to have seen this before though we all know whether I have.

[Eromaveabeara]

IMO, the secret to this device is the constraints.... maintaining a straight line of action

[smazibummigue]

Newton's cradle is a rather interesting device/demonstration

I like the big cover-all words... its just conservation of momentum, LOL
double speak

eg Why does two follow through..2 in 2 out.... easy LOL
and what of three ?...

I am not professing on this one.... I am in awe of Newton.

I'm sorry Zarkov, but I don't know what your point is here.