CM [015] Newton's Cradle
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Transcript of CM [015] Newton's Cradle
© ABCC Australia 2015 www.new-physics.com
NEWTON’S CRADLECM [015] The Motion of Phonons in
© ABCC Australia 2015 www.new-physics.com
Newton’s Cradle
The transfer of phonons is best demonstrated by the setup named after Sir Isaac Newton - the Newton’s cradle.It is available in toy shops and stores associated with geographic and science societies. It contains several steel balls hanged on delicate wires or threads so that they can swing and hit each other straight.
© ABCC Australia 2015 www.new-physics.com
One ball strike
In Newton's cradle five-ball system, one ball is pulled away and is left to fall; it strikes the first ball in the series and comes to nearly a dead stop. The momentum of the first ball disappears and reappears as the momentum of the last ball as it rises into the air.
© ABCC Australia 2015 www.new-physics.com
Starting the motion
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1st Ball drops to hit the 2nd ball
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Phonons pass through the chain
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Phonons lift up the last ball
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The last ball drops back
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The last ball starts the process again in the reversed way
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The Passage of the Phonons
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PASSAGE OF PHONON FROM ONE BOUND PARTICLE TO ANOTHER
The Mechanism of the
© ABCC Australia 2015 www.new-physics.com
Free Particles
The is the scenario of one moving particle hitting another one which is at rest in free space.
The classical picture is like that of a particle moving and hitting a stationary one.
The phonon picture is slightly different in having a phonon mounted on the moving particle.
Classical picture. One particle moving toward another
Phonon picture. One compound moving towards another.
A B
A B
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Sequences
1) Particle A moves close to particle B.
1) Particle B takes over phonon from particle A.
2) Particle B moves & oscillates; particle A being left motionless.
© ABCC Australia 2015 www.new-physics.com
Bound particles in crystal lattice structure
In demonstrating the passage of photon from one particle to the other in matter, we use the simplest crystal lattice structure wherein the core particles are arranged in a perfectly orderly manner. Let’s begin with a group of particle elements space evenly in a single line, and let us assume that in the beginning, they don’t move at all. They interact with each other like there are springs between them.
© ABCC Australia 2015 www.new-physics.com
Passage of phonons in Crystal Structures
The phonon drives the element closer to the next one and so is able to pass onto it. This goes on repeatedly until it reaches the last one.
1-D crystal structure
Phonon causes ion to vibrate and move closer to the next one.
Phonon passes over to the next one and repeats the process again.
© ABCC Australia 2015 www.new-physics.com
THE PHONONThe end of discussions on the
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