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# instantaneous energy stuff

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hi

i have a rather simple question

if i have a bunch of balls lined up so they're touching each other, and i throw a ball on one end of the chain, the ball on the other side of the chain will pop out

take a look at this guy's avatar, err, he has nothing to do with me, im just using his avatar cos i dont know what those desk gizmos are called

http://www.scienceforums.net/forums/member.php?u=5728

now is the energy transfered from one ball to the one on the far end instantaneous? if so, i thought nothing could travel faster than the speed of light

doesnt that mean that if i had a rather long rod, i could poke a message to someone that was quite far away, eg say 1 light second away, then my information would reach the other person 1 second faster than the speed of light

so.... somebody tell me why im wrong?

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hmm

after i posted that, i realised that it could be possible that the energy will move from each individual particles within the balls, bumping onto the next and that to the next at a fast speed.

if so, what if the situation was so that a couple of particles were stuck in a line or at least a group, (eg a heavy atom) so if one particle hit one side with enough force, one particle from the other side will pop out ..... err i supose that's splitting the atom, and i realise that what i mentioned wont happen, but will the transfer of energy be instantaneous?

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hmm

after i posted that' date=' i realised that it could be possible that the energy will move from each individual particles within the balls, bumping onto the next and that to the next at a fast speed.

if so, what if the situation was so that a couple of particles were stuck in a line or at least a group, (eg a heavy atom) so if one particle hit one side with enough force, one particle from the other side will pop out ..... err i supose that's splitting the atom, and i realise that what i mentioned wont happen, but will the transfer of energy be instantaneous?[/quote']

Called a newtons cradle I belive. And I don't think the energy transpher is instantaneous, as it takes time for the kinetic energy of the hitting particle to actually hit it, impulse or something like that. I'm sorry I'm not making much sence. There is also the time taken for the exchange particles to travel between particles.

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hi

i have a rather simple question

if i have a bunch of balls lined up so they're touching each other' date=' and i throw a ball on one end of the chain, the ball on the other side of the chain will pop out

take a look at this guy's avatar, err, he has nothing to do with me, im just using his avatar cos i dont know what those desk gizmos are called

http://www.scienceforums.net/forums/member.php?u=5728

now is the energy transfered from one ball to the one on the far end instantaneous? if so, i thought nothing could travel faster than the speed of light

doesnt that mean that if i had a rather long rod, i could poke a message to someone that was quite far away, eg say 1 light second away, then my information would reach the other person 1 second faster than the speed of light

so.... somebody tell me why im wrong?[/quote']

I think it travels at the speed of sound in that material (steel usually).

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Hey! I'm famous!

Even with truly elastic collisions (e.g. classical collision theory, the billiard ball model) there is an extended time of contact between the balls colliding, in which they compress and distort. The 'elastic' part comes in when they bounce back to their original shape, launching them away from each other. It is during this period of contact that energy is transferred between the balls.

 Whatever you do, don't get him started talking about his balls!
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I think it travels at the speed of sound in that material (steel usually).

I second that I just couldn't remember it at the time...

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That would make sense, as sound is nothing more that that same "newton's cradle" effect but from your throat, through the air, and into someone else's ears. Knocking and nudging air molecules at the same frequency/strength, to make the same sound as you originally made.

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thanks for the replies

thats what i meant when i wrote my first reply after i posted the question

so what if these objects were so dense that it had absolutely no elastic potential, like the atoms are crammed together with no space between them

kinda like a billard ball line where the billard balls are made of neutron stars?

err i just had a thought, if i poked a neutron star, and since they're all crammed and cant bounce off each other, would that turn it into a black hole?

also, are you saying that, say if the speed of sound in steel was 6000ms^-1, if i have a 6km long rod, and i pushed it forward, the push would not be felt on the other side of the rod untill after one second it has been pushed?

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thanks for the replies

thats what i meant when i wrote my first reply after i posted the question

so what if these objects were so dense that it had absolutely no elastic potential' date=' like the atoms are crammed together with no space between them

kinda like a billard ball line where the billard balls are made of neutron stars?

err i just had a thought, if i poked a neutron star, and since they're all crammed and cant bounce off each other, would that turn it into a black hole?

also, are you saying that, say if the speed of sound in steel was 6000ms^-1, if i have a 6km long rod, and i pushed it forward, the push would not be felt on the other side of the rod untill after one second it has been pushed?[/quote']

Not sure about the black hole. When you say poke remember that atoms never actually *touch* they send exchange particles between each other which cannot travel faster than c.

Yes I think that's what we're saying.

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