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A Question about atoms...


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Ok so atoms make up everything in the universe. Air, water, objects, etc.., are all made out of atoms.

 

Now if you have a glass of water, you can stick your finger into the water. If you have a solid object such as a wood door for example you cannot stick your finger into the wooden door.

Is this because the atoms in the water are moving slower then that of the atoms in the door?

 

If so that would mean that if you had an object going the same speed or faster then the speed of the atoms in a solid object the object could go right through a solid object.

For example: You have a door and a ball. The ball is thrown at the door faster then the speed of the atoms traveling in the door, so therefor the ball will go through the door withought leaving a hole, dent, or whatever. This would be possible wouldn't it be?

 

I also have another question that is a little different but still same idea kinda. I know this is not possible but this is just an example thing.

 

Suppose you had some water hovering in the air. Just like 1 gallon of whater in one spot in the air. Know you throw a ball through the water and the ball moved slower then the atoms in the water. Therefor the ball would absorb some of the water and get wet. know assume you throw a ball through the water and the ball travels faster then the speed of the atoms in the water. Wouldn't it be true that the ball would absorb no water and not get wet?

 

Maybe i have something confused, or all wronge lol. I hope i explaned all this good enough, i'm only 14 =/

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Atoms in liquids move FASTER than those in solids.

Atoms in solids are in fixed positions.

The bonds between molecules in solids are stronger than those in liquids (why they're in fixed positions because they don't have enough energy to move very far)

 

The speed of one object hitting another object does not matter, because they will still be moving into each other, if one is in the way of the other they will still hit. So the ball would still get wet.

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Ok well if the atoms in the solid abject are stationary that just leaves this question:

 

Nothing is truly "solid", there is space between all the atoms that make an object. Most of all matter is empty space. So if you were to shoot a ball small enough to fit through the space between the atoms then it could get through the solid object without causing the solid object any damage.

 

It is the same thing with the water. if the ball was small enough to get through the space between the atoms in the water it could get through the water without getting wet.

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It is actually the electrical repulsion between atoms that stops us from moving through an object. As the atoms in say you hand and the atoms in the desk repell eachother then it stops your hand from moving throught it. Also as the atoms in the desk are attracted to each other the force that you put on the desk will travel throughout the desk (thump it with your hand and you will see this - and hear it too as the energy that is moving through the atoms of the desk give some of that energy to the atoms of the air causeing sound).

 

With air and other non solids, the atoms (and molecules) of the substance are less tightly bound to each other (not attractive or repulsive), sometimes they might be attected to each other, but the energy that each atom or molecule has is enough to overcome this attraction (this is what happens when ice melts - you give the water molecules enough energy to overcome their attraction to each other enough to move around). Once this attraction has been broken then as you push on the atoms they will be able to move around and also move past one another (so you don't have to end up moving the entire object). This still take energy to do and we call it viscosity (air resistance if you are talking about air).

 

Because atome and molecules can have either attraction or repulsion to eachother, it is posable to immerse an object in water and it not get wet, simply by applying a coat of molecuels (or atoms) that repell the molecue of water (these are called hydrophobic materials -as they repell water). Also because water is attracted to its self (other water atoms) it can be made to not wet a substance if the attraction of the water molecules to the molecules on the surface is less than the attraction of the water to its self.

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Ok well if the atoms in the solid abject are stationary that just leaves this question:

 

Nothing is truly "solid"' date=' there is space between all the atoms that make an object. Most of all matter is empty space. So if you were to shoot a ball small enough to fit through the space between the atoms then it could get through the solid object without causing the solid object any damage.

 

It is the same thing with the water. if the ball was small enough to get through the space between the atoms in the water it could get through the water without getting wet.[/quote']

 

 

Actually the atoms in a solid are not stationary; Klaynos' comments need a little clarification. The center-of-mass is stationary, but the atoms are vibrating, so they are moving. For a given material it is often true that the atoms in a solid are, on average, moving slower than a liquid, and slower still than a gas, but that is not true in general, especially when comparing different materials, because they have different melting and boiling points, and besides, you can do lots of things with atoms. In my lab, we regularly have atoms of gas moving at only a few cm/sec, because they have been laser-cooled to a few microKelvin, but they are still a gas. The liquid molecules in my body are moving faster, and the atoms at the tip of the soldering iron on the lab bench are probably moving (vibrating) the fastest of all.

 

As far as shooting things through solids, yes, you can do it. As Edtharan notes it is the electrostatic interaction about which you must worry, but it is possible to shoot a neutral particle, like a neutron, through a material, and it will need to basically make a head-on collision with a nucleus to be lost. Whether it is likely to do that depends on the thickness and density of the material, as well as the interaction probability, or cross-section, of the nucleus and energy of the neutron.

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Something that is interesting along these lines is adding velocity to atoms to make them act differently. For example if a throw a glass of water at a concrete wall the water will just splash away. If I run the water through a hi-pressure nozzle, I can use liquid water to cut concrete like butter.

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Something that is interesting along these lines is adding velocity to atoms to make them act differently. For example if a throw a glass of water at a concrete wall the water will just splash away. If I run the water through a hi-pressure nozzle, I can use liquid water to cut concrete like butter.

I believe you are refering to "momentum".

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but it is possible to shoot a neutral particle, like a neutron, through a material, and it will need to basically make a head-on collision with a nucleus to be lost.

 

What if the neutron hits the electrons surrounding the atom, wouldn't it deflect off and change it's path?

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What if the neutron hits the electrons surrounding the atom, wouldn't it deflect off and change it's path?

 

The mass of an electron is miniscule comparing to the mass of a neutron. The momentum change in a neutron if it runs into an electron is negligible.

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The mass of an electron is miniscule comparing to the mass of a neutron. The momentum change in a neutron if it runs into an electron is negligible.

 

 

That's certainly true, and you also have to consider the quantum-mechanical nature of these entities. If there's no interaction they will pass right through each other, because they will act like waves; this is a lot less like pool/billiards/snooker than one might be imagining. With a neutron and electron, there is no electrostatic interaction because the neutron has no charge, but there is a magnetic one, and they can also interact via the weak nuclear force. So you could get scattering, but the cross-section is probably small, and if you did then the comments about the relative masses applies.

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[1] If there is (NO) interaction------ ??????????

 

they will pass right through each other, because they will act like waves;

 

(1) Where & when have you ever see or read of a neutron detected as a wave?

 

[2] but there is a magnetic one [ isn’t that a interaction?]

 

[3] and they can also interact via the weak nuclear force

 

(2 & 3) Noblest Steven Weinberg showed us that the electromagnet and the

 

nuclear-weak force is the one and same.

 

Alpha-137:)

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[1] If there is (NO) interaction------ ??????????

 

they will pass right through each other' date=' because they will act like waves;

 

(1) Where & when have you ever see or read of a neutron detected as a wave?[/quote']

 

Years ago, when I was looking up neutron diffraction using a Bonse-Hart interferometer, because we wanted to use that scheme for atom interferometry. People have made neutrons, atoms and even molecules, interfere. A wave property.

 

[2] but there is a magnetic one [ isn’t that a interaction?]

 

[3] and they can also interact via the weak nuclear force

 

Yes' date=' and please note where I said the cross-section is probably small, i.e. it is unlikely to interact via these mechanisms.

 

(2 & 3) Noblest Steven Weinberg showed us that the electromagnet and the

 

nuclear-weak force is the one and same.

 

(That would be Nobelist, no?) The electroweak unification energy is hundreds of GeV.

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Firstly, Not everything in the universe is made of atoms. In Neutron Stars, they are made up of only neutrons, not atoms. 2ndly, the reason you can put your finger into a liquid and not a solid is becuase a solid has rigid structure, it has its own shape, but a liquid moulds to the shape of its container. A liquid cannot maintain its own shape because the atoms are at a higher temperature, so moving faster, too fast to maintain a rigid shape.

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Nothing is truly "solid"' date=' there is space between all the atoms that make an object. Most of all matter is empty space. So if you were to shoot a ball small enough to fit through the space between the atoms then it could get through the solid object without causing the solid object any damage.

[/quote']

 

Yes. That is why X-rays can pass through some matter. The wavelength of the light is so small it slips right through. (It is stopped by materials which are more dense because there is less space in between the atoms.)

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