So the aircraft can handle two iPad that are in the hands of trained pilots who ensure that the wifi and bluetooth transmitters are turned off. That does not mean that the aircraft can handle most of the 300+ passengers with cell phones, games machines, tablets and laptops all transmitting at the same time. A little noise being OK does not mean a lot of noise is also OK.
Electrical interference is a known cause for malfunctioning electronic equipment. That is why we have emission and shielding standards. That is the link between electrical noise and flight instruments. The issue is that there has been little or no testing to find out how large scale wireless transmissions react inside an aircraft and if it will cause instrument issues.
On the other hand, there is no logical link between food service an instrument malfunction.
Sample size is not the issue it is the testing parameters. Sure airplanes have been tested where 18% of the passengers had their cell phones turned on. The issue is has it been tested when 90% or the passengers have their cell phones turned on plus 40% of the passengers with games devices and or tablets and or laptops. Safety at one level of noise does not mean safety at all levels of noise.
As an example there are certain poisons that are allowed in our food at specific levels. At those levels the body can handle it with no ill effect. At higher levels they can kill. Low level noise is safe in aircraft. Much higher level noise might not be but that line, if there is one, has not been tested.
So by your numbers 18% of the cell phones are turned on. I agree that has been proven safe. What happens when five times as many phones are turned on just before landing and all of them are transmitting feverishly looking for a cell tower? Don't you think the noise would increase quite a bit? It is not a one to one ratio of devices to noise but it may double or triple. Testing at higher levels needs to be done on all aircraft to be of any scientific relevance. Testing at one noise level does not mean all noise levels are safe.
That's the part that always gets me. If they believed to even 0.001% of a chance that the bottle of water I'm drinking from is a potentially explosive material, would they really tolerate having me toss it in a plastic garbage can next to them?
The reason it works is that since liquids are confiscated terrorist will not waste their time and resources trying to get binary explosives on the plane.
Yes, 100 devices does not equal 100 times the noise. There is a point that you missed though; 100 devices also does not equal the noise of one device. This is evidenced by this quote from your post "Noise from these devices increases less and less as you add more." While the increase is not one to one the noise does build up. If you get enough noise there may be problems. The testing has not been done to show where this noise line is.
Not when safety is an issue. Should drug companies be able to sell any drug they want? Should car manufacturers be able to sell any car they want? Should restaurants be able to ignore food inspectors? Should chemical manufacturers be able to sell any chemical they want? Should people be able to drive any speed they want anywhere? Should people be able to build houses any way they want? I would say no to all of these. Safety regulations are there to save people's lives. The credo of any safety organization is "Prove it is safe and then we will talk". The first job of the FAA is safety not liberty.
Big difference. Free speech can not cause aircraft instruments to malfunction and the plane to fly into the ground killing hundreds of people. The opposite is also true. One could get drug companies saying "Prove that this drug does not harm people or let us sell it". It is a risk reward issue. People have lived quite happily on aircraft before wireless devices were invented and they can continue to do so with their wireless devices turned off. If the wireless industry wants to be on aircraft let them pay for the testing to prove that they won't kill people.
When the plane crashes due to a vibration induced failure you will sing a different tune. Much of the cost of avionics is due to the necessity of making them much more robust than a desktop PC. If you PC glitches you just reboot. Try that on short final at night in the rain. The main factors that go into the high costs of avionics are as follows; 1. Large design costs due to necessity of robustness. 2. Large design costs due to the need for FAA certification. 3. Large manufacturing costs to due small production runs. 4. Large manufacturing costs due to the necessity of components that can deal with vibration and significant G forces (you don't want you glass cockpit to die after a hard landing). 5. Large manufacturing costs due to stringent testing requirements for each instrument sold.
Sure you can buy a PC for a lot less but would you bet your life on it?
How does electric charge flow when there is no conductor? If the tube is crimped so that the sides are touching there is no space for the liquid. You stated that yourself. Then you stated that there is enough room for "electrons to flow". If two attoms of the conductive fluid are more that 1/2mm apart the charge will not transfer between them. If a crimp is string enough to stop water at 50 psi it is strong enough to separate conductor under no pressure.
As for your experiment, I do not have the equipment to prove that there is no air in the tube so any results would be suspect at best. You still have not described how a n elastic material that can elongate 800% can't bulge by less than 2%.
you are going to have to squeeze it so tightly that not even a single molecule of thickness exists inside the body of the tube across the gap you are squeezing. This is quite a bit thinner than what you need to stop water pressure for a garden hose,
If the crimp is tight enough to stop molecules of water under pressure the why is it not tight enough to stop molecules of metal under very little pressure? Since it is stopping the liquid metal, the pinch would separate it.
There are two points you repeatedly get wrong; 1. Electrons do not flow outside of a conductor. 2. Elastic materials stretch in all directions. Go to a high school or university and ask a physics instructor. They will explain it much better so that you can understand basic physics.
Perhaps you might want to read a little on how electrical current flows. The crimp does not stop the flow of electrons it separates the conductor so that there is no conductive material for the charge to flow through. Electrons to not flow through air except at very high voltages. Outside of a conductor dielectric breakdown must occur for current to flow.. You keep concentrating on the width of the crimp but ignore the length. If I can create a gap in the conductor fluid 1/2 mm long no matter how thick the gap no electrical charge will flow. The potential needed to jump a mm of air is about 3kV. A 5V charge would not make it. It is even worse when there is not enough space for air to be so there is no possibility if ionization. You can not seem to get it through your head that electron flow is not separate from the atoms that they make up. Electrons are not tiny bits of matter that flow like water. They are charges that move from atom to atom in material that readily accepts and releases charges, conductors, and is stopped by materials that do not exchange charges well, insulators, What you continue to ignore is that if there is no conductor, at the voltages we are talking about, there is no charge flow.
From the summary: "First it was the sex offenders being mapped using public records, now it seems to be gun owners — I wonder who will be next? It seems a newspaper in New York has published an interactive map with the names and addresses of people with [handguns]." Why the "[handguns]"? Why change what was submitted? Why change the real subject of the article, a map of " individuals with handgun or pistol permits" to "handguns"? It is much less accurate and sensationalistic. Just because someone has a permit does not mean they always have a gun. For example, people who carry handguns due to their job may not have one at home. They may be target shooters that need the permit to transport their pistols from range to range, Permit holders are much more likely to have a handgun at home but it is not a sure thing like the summary states.
Try reading the whole sentence not just every other word. Here is the quote; "Note that these figures include accidental shootings, suicides, even acts of self-defense, as well as crimes." The stats includ those numbers and are not just those numbers. It means they include all forms of gun death and injury and not just crime.
If you are such a materials expert how can one allow the tube to elongate but constrain it from bulging? You can't. The scenario you propose is only a problem it it bulged easily like a latex balloon. It is not a problem if it takes a reasonable amount of pressure to bulge. The couple of ounces of liquid metal in a tube will create a few psi in the bottom end of a vertical wire. Now say you put 30PSI on a small section of the wire. That small section will flatten and the rest will bulge slightly. Look at the math I showed you in previous posts. To accommodate a 1/2" pinch in a 5' wire it would have to bulge by less than 2%. Not a big deal in a tube that can elongate 800%.
Have you ever played with elastic tubes? I doubt it. So how are you such an expert in their properties? I have in my possession some silicone tubing that would work quite well for this application. It has a thick wall to resist bulging due to the weight of the liquid, will elongate quite well and will also bulge without breaking if enough pressure is applied. Have you looked at a real piece of tubing or are you just guessing? The advancement is not the tubing it is the alloy in the conductor.
So far you have been incorrect in how electron charge flows (the electron themselves do not), You have no idea how elastics work (if the can elongate along a tube they can also elongate around the circumference causing bulges). You have no idea how to tune elastics (the tube can be stiff enough to support the weight of the liquid but still deform under enough pressure). You have shown that you can not differentiate shearing force and crushing force. You have no concept of how small a change in the tube would be required to accommodate a crimp. So far you have shown no understanding of electricity, mathematics, physics or materials science and no desire to learn therefore this will be my last post. I am tired of talking to a brick wall.
It is simple. the section one is not pinching will expand to accommodate the liquid. The liquid from the area being pinched goes into the area not being pinched which bulges to accommodate the liquid. It is called elasticity. Whether it is lengthened or not is irrelevant. The fact is that if the tube can lengthen means it can also bulge. You can't constrain an elastic material to only lengthen in one direction. If the tube can lengthen it can also increase circumference. The tube can increase circumference to accommodate the liquid displaced by the pinch. I am not talking about pinching the whole tube flat as that is impossible. As I stated, if one pinched 5% of the length of the tube flat there is plenty of elasticity to accommodate the shift in fluid.
The cross section reduces because the fluid has a place to go in the longer tube. If one pushed the fluid up to one end of the tube the cross section would get bigger and the wall thickness thinner. Take a long thin balloon and fill it with water. Hold both ends and pull. It will elongate. Grab the middle and squeeze. The ends will bulge which will accommodate the liquid. There is no magic about it. It is simple elastic physics. Anything that can elongate can also bulge.
Variable naming standards reduce the guesswork when referring to variable. If it is all caps it is a constant and can not be changed. If I am in some code and I need to modify or refer to the variable that hold the "total cost" it could be total_cost, totalCost or totalcost depending on how the programmer declared it. With a coding standard there is no guess work. There would be only one choice. If the first letter is caps it is a class name and the method is static. I don't have to check. I need to access an instance variable, Is there a get and set method? What does the standard say?
Wasting hours on code reviews is caused by people refusing to follow the standard. It is a people problem not a standard problem.
Just because it is a standard does not mean it is a good standard. There are bad standards that do cause issue but some people love them. Coding standards are a balance between pedantic nit pickers and wild free spirits. Do I really care is there is a space after the semicolon in a for statement? No but I do care about an if-then-else statement on one line. Consistency within an organization is very important. I call it "hit by a bus" theory. Code should be written so that if you are hit by a bus someone else can read and understand it.
The issue is that what one programmer calls common sense another will call stupid. Standards create consistent code and good standards create readable code.
if you are pinching it, then it *ISN'T* free to elongate along the region that you are pinching it.
So what? My point is that if it can elongate it can also bulge and the liquid displaces from the pinch will be accommodation by deforming the rest of the tube.
The result is a shearing force that will almost certainly sever it just as certainly as scissors would.
Yes scissors would be a shearing force but what I am talking about is a crushing force. Take the tube, put it into a C clamp and tighten. The tube will collapse long before it cuts. That is a crushing force. You really need to learn some physics. A shearing force is high pressure over a very narrow area. A crushing force is also high pressure but over a much larger area. Shearing forces cut while crushing forces generally cause deformation but do not cut. I have some silicone tubing that is about 1/8" outside diameter. It is very stretchy and probably would accommodate the liquid conductor quite well. I can elongate it quite far and I can crush it closed with my fingers without cutting it..
There's a handful of reasons why this is so, not the least of which is the fact that this isn't like a hose where the liquid you displace by pinching can flow out of either end... it's a flexible container, but it's closed on either end.
Yes it is but it is also a flexible container that can change it cross section. If you press one part of the tube another part of the tube can balloon out and accommodate the liquid.
The amount that the wire would have to stretch to be pinched to such thinness to make room for all of the displaced liquid would, again, tear apart the wire itself unless it were made out of an abnormally ductile substance (which rubber is not).
The tube is very ductile. It can elongate 8 times it's original length. Say one has a 5" long wire and 1/2" is pinched flat. The rest of the wire would have to accommodate.5/59.9= 8% more liquid. That would mean that the rest of the wire would have to increase its diameter by 1.6%. That would not be difficult for a material that can elongate by 800%.
Industrial situations are not the problem. All it takes is a loop in the wire, a closed door or someone stepping on the tube. I think what may be causing the issue is that you are thinking of large tubes while I am thinking of tubes around 1/8" which would replace headphone wiring.
Which I am asserting that no normal amount of pressure could hope to achieve without actually breaking the wire in the first place.
A plastic tube that is malleable enough to stretch 8 times its length is malleable enough to be crushed flat without "breaking". Take some rubber tubing, fill it with water and crimp it like the picture. That is exactly what this device is. It is not a wire with a solid core; the core is liquid and will move out of the way of a crimp.
Enough to stop the liquid from flowing through the gap, yes
This shows how little you understand the concept. The liquid does not flow at all. The electrons cascade through the liquid. Where there is no liquid, as in a pinch, there is no electron flow. If the sides of the tube are touching each other what atoms are exchanging electrons so the charge moves? It isn't the tubing as that is an insulator. Electrons do not flow. They jump from one atom to another. If two atoms of the liquid metal are not touching there will be no electron flow. With enough energy electrons can cross short gaps. That is called a spark and takes a lot of voltage to accomplish. That is far beyond the voltages in a headphone wire.
Melting would only occur if there was enough power in the wire to create the heat. Headphone work at low voltage and low amperage. The most powerful headphones I found were 200mW. That is far from enough power to melt plastic. Sure if it was being used for household current it might occur but that is not what this device is designed for.
The point you miss is that electrons do not flow through air very well; that would be called a spark. The sides of the tube do not have to be close enough to cut off the flow of electrons; it just has to be small enough to separate the liquid conductor. If there is a gap in the conductor there will be no electron flow.
As for melting the insulation, that would require a lot of power to push the electrons against the resistance to create enough heat. Most headphones do not have enough power to do that as electron flow would just stop. Another point is that if the tube is crimped quickly it will act like a switch and there will not be enough time for heat to build up.
As for the scenario; did you look at the picture in a previous post? It does not take a lot of force. All it requires is a loop and pulling the ends a bit to create a pinch in the tube much like is done to crimp off a water hose. There is a point at which the sides are close enough to stop water flow. That same kind of crimp is enough to separate the liquid conductor. Remember that the tube elongates 8 time that means it is pretty elastic. That means that it would crush pretty easily. I bet I could crush the tubing with my fingers enough to separate the conducting fluid.
Metals that make springs make poor conductors. There is also the fact that springs have a stress limit. Pull to hard and they stay straight. For a spring to elongate it takes a large diameter spring relative to the diameter of the wire. The article states 8 times. That means the coil must be at least 2.5 times the diameter of the wire. Factor in double that so that the wire does will return to a coil makes it 5 times. The 1/8" wire would be a coil over 1/2" in diameter. Not so great for portable headphones.
If the tube is crushed flat there would be no liquid metal there for the electrons to flow through. Sorry but electrons flow from atom to atom. If the pinch is wide enough the electrons will not be able to jump the gap. The electron flow needs a continuous conductor. if the pinch creates a gap of 1/4 of a mm in the liquid the flow of electrons will be stopped.
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So the aircraft can handle two iPad that are in the hands of trained pilots who ensure that the wifi and bluetooth transmitters are turned off. That does not mean that the aircraft can handle most of the 300+ passengers with cell phones, games machines, tablets and laptops all transmitting at the same time. A little noise being OK does not mean a lot of noise is also OK.
Electrical interference is a known cause for malfunctioning electronic equipment. That is why we have emission and shielding standards. That is the link between electrical noise and flight instruments. The issue is that there has been little or no testing to find out how large scale wireless transmissions react inside an aircraft and if it will cause instrument issues.
On the other hand, there is no logical link between food service an instrument malfunction.
Sample size is not the issue it is the testing parameters. Sure airplanes have been tested where 18% of the passengers had their cell phones turned on. The issue is has it been tested when 90% or the passengers have their cell phones turned on plus 40% of the passengers with games devices and or tablets and or laptops. Safety at one level of noise does not mean safety at all levels of noise.
As an example there are certain poisons that are allowed in our food at specific levels. At those levels the body can handle it with no ill effect. At higher levels they can kill. Low level noise is safe in aircraft. Much higher level noise might not be but that line, if there is one, has not been tested.
So by your numbers 18% of the cell phones are turned on. I agree that has been proven safe. What happens when five times as many phones are turned on just before landing and all of them are transmitting feverishly looking for a cell tower? Don't you think the noise would increase quite a bit? It is not a one to one ratio of devices to noise but it may double or triple. Testing at higher levels needs to be done on all aircraft to be of any scientific relevance. Testing at one noise level does not mean all noise levels are safe.
That's the part that always gets me. If they believed to even 0.001% of a chance that the bottle of water I'm drinking from is a potentially explosive material, would they really tolerate having me toss it in a plastic garbage can next to them?
The reason it works is that since liquids are confiscated terrorist will not waste their time and resources trying to get binary explosives on the plane.
Yes, 100 devices does not equal 100 times the noise. There is a point that you missed though; 100 devices also does not equal the noise of one device. This is evidenced by this quote from your post "Noise from these devices increases less and less as you add more." While the increase is not one to one the noise does build up. If you get enough noise there may be problems. The testing has not been done to show where this noise line is.
Liberty ALWAYS comes first.
Not when safety is an issue.
Should drug companies be able to sell any drug they want?
Should car manufacturers be able to sell any car they want?
Should restaurants be able to ignore food inspectors?
Should chemical manufacturers be able to sell any chemical they want?
Should people be able to drive any speed they want anywhere?
Should people be able to build houses any way they want?
I would say no to all of these. Safety regulations are there to save people's lives.
The credo of any safety organization is "Prove it is safe and then we will talk". The first job of the FAA is safety not liberty.
Big difference. Free speech can not cause aircraft instruments to malfunction and the plane to fly into the ground killing hundreds of people. The opposite is also true. One could get drug companies saying "Prove that this drug does not harm people or let us sell it". It is a risk reward issue. People have lived quite happily on aircraft before wireless devices were invented and they can continue to do so with their wireless devices turned off. If the wireless industry wants to be on aircraft let them pay for the testing to prove that they won't kill people.
When the plane crashes due to a vibration induced failure you will sing a different tune. Much of the cost of avionics is due to the necessity of making them much more robust than a desktop PC. If you PC glitches you just reboot. Try that on short final at night in the rain. The main factors that go into the high costs of avionics are as follows;
1. Large design costs due to necessity of robustness.
2. Large design costs due to the need for FAA certification.
3. Large manufacturing costs to due small production runs.
4. Large manufacturing costs due to the necessity of components that can deal with vibration and significant G forces (you don't want you glass cockpit to die after a hard landing).
5. Large manufacturing costs due to stringent testing requirements for each instrument sold.
Sure you can buy a PC for a lot less but would you bet your life on it?
How does electric charge flow when there is no conductor? If the tube is crimped so that the sides are touching there is no space for the liquid. You stated that yourself. Then you stated that there is enough room for "electrons to flow". If two attoms of the conductive fluid are more that 1/2mm apart the charge will not transfer between them. If a crimp is string enough to stop water at 50 psi it is strong enough to separate conductor under no pressure.
As for your experiment, I do not have the equipment to prove that there is no air in the tube so any results would be suspect at best. You still have not described how a n elastic material that can elongate 800% can't bulge by less than 2%.
you are going to have to squeeze it so tightly that not even a single molecule of thickness exists inside the body of the tube across the gap you are squeezing. This is quite a bit thinner than what you need to stop water pressure for a garden hose,
If the crimp is tight enough to stop molecules of water under pressure the why is it not tight enough to stop molecules of metal under very little pressure? Since it is stopping the liquid metal, the pinch would separate it.
There are two points you repeatedly get wrong;
1. Electrons do not flow outside of a conductor.
2. Elastic materials stretch in all directions.
Go to a high school or university and ask a physics instructor. They will explain it much better so that you can understand basic physics.
Perhaps you might want to read a little on how electrical current flows. The crimp does not stop the flow of electrons it separates the conductor so that there is no conductive material for the charge to flow through. Electrons to not flow through air except at very high voltages. Outside of a conductor dielectric breakdown must occur for current to flow.. You keep concentrating on the width of the crimp but ignore the length. If I can create a gap in the conductor fluid 1/2 mm long no matter how thick the gap no electrical charge will flow. The potential needed to jump a mm of air is about 3kV. A 5V charge would not make it. It is even worse when there is not enough space for air to be so there is no possibility if ionization. You can not seem to get it through your head that electron flow is not separate from the atoms that they make up. Electrons are not tiny bits of matter that flow like water. They are charges that move from atom to atom in material that readily accepts and releases charges, conductors, and is stopped by materials that do not exchange charges well, insulators, What you continue to ignore is that if there is no conductor, at the voltages we are talking about, there is no charge flow.
From the summary:
"First it was the sex offenders being mapped using public records, now it seems to be gun owners — I wonder who will be next? It seems a newspaper in New York has published an interactive map with the names and addresses of people with [handguns]."
Why the "[handguns]"? Why change what was submitted? Why change the real subject of the article, a map of " individuals with handgun or pistol permits" to "handguns"? It is much less accurate and sensationalistic. Just because someone has a permit does not mean they always have a gun. For example, people who carry handguns due to their job may not have one at home. They may be target shooters that need the permit to transport their pistols from range to range, Permit holders are much more likely to have a handgun at home but it is not a sure thing like the summary states.
Try reading the whole sentence not just every other word. Here is the quote; "Note that these figures include accidental shootings, suicides, even acts of self-defense, as well as crimes." The stats includ those numbers and are not just those numbers. It means they include all forms of gun death and injury and not just crime.
Sorry but you are a moron.
If you are such a materials expert how can one allow the tube to elongate but constrain it from bulging? You can't. The scenario you propose is only a problem it it bulged easily like a latex balloon. It is not a problem if it takes a reasonable amount of pressure to bulge. The couple of ounces of liquid metal in a tube will create a few psi in the bottom end of a vertical wire. Now say you put 30PSI on a small section of the wire. That small section will flatten and the rest will bulge slightly. Look at the math I showed you in previous posts. To accommodate a 1/2" pinch in a 5' wire it would have to bulge by less than 2%. Not a big deal in a tube that can elongate 800%.
Have you ever played with elastic tubes? I doubt it. So how are you such an expert in their properties? I have in my possession some silicone tubing that would work quite well for this application. It has a thick wall to resist bulging due to the weight of the liquid, will elongate quite well and will also bulge without breaking if enough pressure is applied. Have you looked at a real piece of tubing or are you just guessing? The advancement is not the tubing it is the alloy in the conductor.
So far you have been incorrect in how electron charge flows (the electron themselves do not), You have no idea how elastics work (if the can elongate along a tube they can also elongate around the circumference causing bulges). You have no idea how to tune elastics (the tube can be stiff enough to support the weight of the liquid but still deform under enough pressure). You have shown that you can not differentiate shearing force and crushing force. You have no concept of how small a change in the tube would be required to accommodate a crimp. So far you have shown no understanding of electricity, mathematics, physics or materials science and no desire to learn therefore this will be my last post. I am tired of talking to a brick wall.
It is simple. the section one is not pinching will expand to accommodate the liquid. The liquid from the area being pinched goes into the area not being pinched which bulges to accommodate the liquid. It is called elasticity. Whether it is lengthened or not is irrelevant. The fact is that if the tube can lengthen means it can also bulge. You can't constrain an elastic material to only lengthen in one direction. If the tube can lengthen it can also increase circumference. The tube can increase circumference to accommodate the liquid displaced by the pinch. I am not talking about pinching the whole tube flat as that is impossible. As I stated, if one pinched 5% of the length of the tube flat there is plenty of elasticity to accommodate the shift in fluid.
The cross section reduces because the fluid has a place to go in the longer tube. If one pushed the fluid up to one end of the tube the cross section would get bigger and the wall thickness thinner.
Take a long thin balloon and fill it with water. Hold both ends and pull. It will elongate. Grab the middle and squeeze. The ends will bulge which will accommodate the liquid. There is no magic about it. It is simple elastic physics. Anything that can elongate can also bulge.
Variable naming standards reduce the guesswork when referring to variable.
If it is all caps it is a constant and can not be changed.
If I am in some code and I need to modify or refer to the variable that hold the "total cost" it could be total_cost, totalCost or totalcost depending on how the programmer declared it. With a coding standard there is no guess work. There would be only one choice.
If the first letter is caps it is a class name and the method is static. I don't have to check.
I need to access an instance variable, Is there a get and set method? What does the standard say?
Wasting hours on code reviews is caused by people refusing to follow the standard. It is a people problem not a standard problem.
Just because it is a standard does not mean it is a good standard. There are bad standards that do cause issue but some people love them. Coding standards are a balance between pedantic nit pickers and wild free spirits. Do I really care is there is a space after the semicolon in a for statement? No but I do care about an if-then-else statement on one line. Consistency within an organization is very important. I call it "hit by a bus" theory. Code should be written so that if you are hit by a bus someone else can read and understand it.
The issue is that what one programmer calls common sense another will call stupid. Standards create consistent code and good standards create readable code.
if you are pinching it, then it *ISN'T* free to elongate along the region that you are pinching it.
So what? My point is that if it can elongate it can also bulge and the liquid displaces from the pinch will be accommodation by deforming the rest of the tube.
The result is a shearing force that will almost certainly sever it just as certainly as scissors would.
Yes scissors would be a shearing force but what I am talking about is a crushing force. Take the tube, put it into a C clamp and tighten. The tube will collapse long before it cuts. That is a crushing force. You really need to learn some physics. A shearing force is high pressure over a very narrow area. A crushing force is also high pressure but over a much larger area. Shearing forces cut while crushing forces generally cause deformation but do not cut. I have some silicone tubing that is about 1/8" outside diameter. It is very stretchy and probably would accommodate the liquid conductor quite well. I can elongate it quite far and I can crush it closed with my fingers without cutting it..
There's a handful of reasons why this is so, not the least of which is the fact that this isn't like a hose where the liquid you displace by pinching can flow out of either end... it's a flexible container, but it's closed on either end.
Yes it is but it is also a flexible container that can change it cross section. If you press one part of the tube another part of the tube can balloon out and accommodate the liquid.
The amount that the wire would have to stretch to be pinched to such thinness to make room for all of the displaced liquid would, again, tear apart the wire itself unless it were made out of an abnormally ductile substance (which rubber is not).
The tube is very ductile. It can elongate 8 times it's original length. Say one has a 5" long wire and 1/2" is pinched flat. The rest of the wire would have to accommodate .5/59.9= 8% more liquid. That would mean that the rest of the wire would have to increase its diameter by 1.6%. That would not be difficult for a material that can elongate by 800%.
Industrial situations are not the problem. All it takes is a loop in the wire, a closed door or someone stepping on the tube. I think what may be causing the issue is that you are thinking of large tubes while I am thinking of tubes around 1/8" which would replace headphone wiring.
Which I am asserting that no normal amount of pressure could hope to achieve without actually breaking the wire in the first place.
A plastic tube that is malleable enough to stretch 8 times its length is malleable enough to be crushed flat without "breaking". Take some rubber tubing, fill it with water and crimp it like the picture. That is exactly what this device is. It is not a wire with a solid core; the core is liquid and will move out of the way of a crimp.
Enough to stop the liquid from flowing through the gap, yes
This shows how little you understand the concept. The liquid does not flow at all. The electrons cascade through the liquid. Where there is no liquid, as in a pinch, there is no electron flow. If the sides of the tube are touching each other what atoms are exchanging electrons so the charge moves? It isn't the tubing as that is an insulator. Electrons do not flow. They jump from one atom to another. If two atoms of the liquid metal are not touching there will be no electron flow. With enough energy electrons can cross short gaps. That is called a spark and takes a lot of voltage to accomplish. That is far beyond the voltages in a headphone wire.
Melting would only occur if there was enough power in the wire to create the heat. Headphone work at low voltage and low amperage. The most powerful headphones I found were 200mW. That is far from enough power to melt plastic. Sure if it was being used for household current it might occur but that is not what this device is designed for.
The point you miss is that electrons do not flow through air very well; that would be called a spark. The sides of the tube do not have to be close enough to cut off the flow of electrons; it just has to be small enough to separate the liquid conductor. If there is a gap in the conductor there will be no electron flow.
As for melting the insulation, that would require a lot of power to push the electrons against the resistance to create enough heat. Most headphones do not have enough power to do that as electron flow would just stop. Another point is that if the tube is crimped quickly it will act like a switch and there will not be enough time for heat to build up.
As for the scenario; did you look at the picture in a previous post? It does not take a lot of force. All it requires is a loop and pulling the ends a bit to create a pinch in the tube much like is done to crimp off a water hose. There is a point at which the sides are close enough to stop water flow. That same kind of crimp is enough to separate the liquid conductor. Remember that the tube elongates 8 time that means it is pretty elastic. That means that it would crush pretty easily. I bet I could crush the tubing with my fingers enough to separate the conducting fluid.
Metals that make springs make poor conductors. There is also the fact that springs have a stress limit. Pull to hard and they stay straight. For a spring to elongate it takes a large diameter spring relative to the diameter of the wire. The article states 8 times. That means the coil must be at least 2.5 times the diameter of the wire. Factor in double that so that the wire does will return to a coil makes it 5 times. The 1/8" wire would be a coil over 1/2" in diameter. Not so great for portable headphones.
If the tube is crushed flat there would be no liquid metal there for the electrons to flow through. Sorry but electrons flow from atom to atom. If the pinch is wide enough the electrons will not be able to jump the gap. The electron flow needs a continuous conductor. if the pinch creates a gap of 1/4 of a mm in the liquid the flow of electrons will be stopped.