Superconductivity

[lajoswinkler]

I bet the whole confusion resides in the fact that people tend to explain force with their hands, and knowing that holding something heavy or pushing against something uses chemical energy stored in our bodies, people think that acting with force requires converting energy.

That's only because people generally don't know how muscles work. A hand pushing against something might seem stationary and thus violating the whole "work is energy over distance" thing, but it's just because you're looking at a black box model. If you could see the muscle at a molecular level, you'd see protein machines constantly converting energy by hydrolising adenosine triphosphate into adenosine diphosphate and phosphate which provides chemical energy for that action.

Look at this video and it will be clear to you.

NHF, but some of you here know physics, but don't really know how to explain it. Being an educator requires interdisciplinary knowledge and approach.

[peadar1987]

Just no. Energy isn't work. Work can be done by converting one form of energy into another however.

Energy expended = work done. Or alternatively, energy = work available to be done. The unit of both is the Joule. You are right, in the most pedantic sense of the word, but it is completely clear that Speed understands the subject, and attacking him on the smallest imaginable point whilst ignoring the rest of his post isn't going to enhance your understanding.

[Jovus]

Oh, and by the way, in something mind blowing that even most electrical engineers don't know about (even those that study EM field theory!), is the connection between electromagnetics and Special Relativity. Magnetic fields arise from electric fields through length contraction of moving charges, and so, in very real way, are nothing but electric fields themselves. All of electromagnetics can be derived from Coulomb's law and Special Relativity. In fact, I think I read somewhere that one of the things that inspired Einstein was his conviction, eventually proven correct, that electric fields and magnetic fields were in fact the same phenomenon.

BTW I am an electrical engineer myself so I know what I'm talking about.

...wow, I'm surprised that people in the field don't know this. The whole creation of special relativity was to give an elegant explanation that negates the need to encrust the laws of electromagnetics with the Lorenze Force Law.

ETA: Though I wouldn't say that magnetic fields are in any way nothing but electrical fields themselves. They're definitely caused by the movement of electrical fields, but the movement of a thing is different from the thing itself. (The velocity of your car is not your car.) This is a physically important difference as well in this case, given as magnetic fields do no work.

Edited February 4, 2015 by Jovus

[rtxoff]

Energy expended = work done. Or alternatively, energy = work available to be done. The unit of both is the Joule. You are right, in the most pedantic sense of the word, but it is completely clear that Speed understands the subject, and attacking him on the smallest imaginable point whilst ignoring the rest of his post isn't going to enhance your understanding.

Just no, energy is not expended while performing work you can't destroy energy. I know people use that term every day but it is not correct. Also his statment that energy=work is not correct. Sorry i can't change the laws of physics and make that to be correct. BTW i am not attacking anyone. This is a civilized discussion so far ignoring the fact that most of you accusing me of beeing confused

No worries no offense taken.

[cpast]

Just no, energy is not expended while performing work you can't destroy energy. I know people use that term every day but it is not correct. Also his statment that energy=work is not correct. Sorry i can't change the laws of physics and make that to be correct. BTW i am not attacking anyone. This is a civilized discussion so far ignoring the fact that most of you accusing me of beeing confused

No worries no offense taken.

You can't destroy energy in a closed system. When someone talks about expending energy, they're not talking about a closed system. A system loses energy when it does work on its surrounding environment. The energy goes to the surrounding environment; when work is done on an open system, the system gains energy. Energy lost or gained = work done by or done on the system. From any non-pedantic standpoint, energy = work; energy represents the ability to do work on something, and a system loses energy when it does work on its environment (i.e. exerts a force over a distance). It's not at all wrong to talk about something gaining or losing energy, because not everything is a closed system. Is the confusion you have related to that?

Edited February 4, 2015 by cpast

[N_las]

Whether something is energy or work just depends on the context and the perspective. In the sense of this topic (levitating magnets), it is perfectly fine to say that you don't need energy, because you don't need work. Work, energy, enthalphy, they are all measured in joule, and they just differ in some small nuance.

The kinetic energy of a moving body: E = 0.5 m v^2

The work needed to accelerate a body to that velocity: W = 0.5 m v^2

[-Velocity-]

Just no. Energy isn't work. Work can be done by converting one form of energy into another however.

So you ignore all my truthful statements and instead focus on a specific interpretation of a mostly irrelevant part of what I had to say, and try to point out a flaw in the reasoning of the irrelevant part. By the way, that is not an argument method that leads to any kind of intelligent discourse, or that is used in an intelligent discussion. It's a distraction "tactic" used by people who don't have a real counter argument, and who don't want to address the real topic of discussion because they don't understand the topic or know they would lose.

To address your pointless nitpick, work is a quantity of energy. The units of energy are Joules and the units of work are Joules. If you interpret my statement of "Energy = work" as being all energy in a closed system, an interpretation no reasonable person would make, then of course that is not correct because globally, energy is conserved, and so this interpretation tells you nothing. No one with a technical background would make the nitpick you did, because it's silly and pointless, and everyone (else) knows exactly what I meant by it.

Anyway, I'm not wasting any more time on you, you are a case of someone who refuses to learn.

Edited February 4, 2015 by |Velocity|

[KSK]

Just no, energy is not expended while performing work you can't destroy energy. I know people use that term every day but it is not correct. Also his statment that energy=work is not correct. Sorry i can't change the laws of physics and make that to be correct. BTW i am not attacking anyone. This is a civilized discussion so far ignoring the fact that most of you accusing me of beeing confused

No worries no offense taken.

From Wikipedia: "The joule is the SI unit of energy, based on the amount transferred to an object by the mechanical work of moving it 1 metre against a force of 1 newton."

I take a weight and lift it against gravity (or to borrow an example from this thread, I take a book, lift it against gravity and place it on a table) I have applied a force over a distance so I have done work. The book has gained gravitational potential energy because it is now higher than it was. The amount of work I did is equal to the amount of gravitational potential energy imparted to the book.

In order to apply that force and do that work, my muscles required energy - see lajoswinkler's post for the fine details. Energy is conserved overall - the energy expended by my muscles will be equal to the energy imparted to the book + wasted thermal energy (because my muscles are not 100% efficient).

Alternatively, I have inefficiently converted chemical potential energy into gravitational potential energy, doing work in the process.

[GoSlash27]

Just no, energy is not expended while performing work you can't destroy energy. I know people use that term every day but it is not correct. Also his statment that energy=work is not correct. Sorry i can't change the laws of physics and make that to be correct. BTW i am not attacking anyone. This is a civilized discussion so far ignoring the fact that most of you accusing me of beeing confused

No worries no offense taken.

If you are not confused, then I'm missing something. You stated earlier that "you need energy to build up a force". This is not the sort of statement that someone who's not confused would make.

A current flowing is generating a magnetic field. The same magnetic field is exists in a permanent magnet without the flow of current.

In one case there is energy involved in the other not? What is this black magic?

^ Were you looking for an answer to this question, or is it merely rhetorical?

If it's an actual question you'd like answered, then you are, indeed confused and we're willing to help you understand... at least until our patience wears thin. If it's *not* an actual question you'd like answered, then why did you ask?

Scratchin' mah head

-Slashy

Edited February 4, 2015 by GoSlash27

[rtxoff]

If it's *not* an actual question you'd like answered, then why did you ask?

Scratchin' mah head

By carefully reading the whole thread from the beginning to the end you might find an answer for your question. And if not it really doesn't matter, it's not like the world will stop to rotate because of that.

But this is already off topic now and also i think that nothing relevant that was not already mentioned can be added anymore to this thread beside maybe this:

Thanks to Aethon for the link.

[PB666]

Sounds to me like you've just described a particle accelerator.

^

In specific as particles approach the speed of light their mass increases, force created by the electromagnets are used to push the charge particles to the center of the stream.

As for the perpetual motion machine (clears throat) no.

Superconducters release enough heat and absorb enough heat to burn of coolant, the electrons may magnetize for a long period but not indefinately.

[LordFerret]

... as long as there was liquid nitrogen in the bath - it would run...

^

In specific as particles approach the speed of light their mass increases, force created by the electromagnets are used to push the charge particles to the center of the stream.

As for the perpetual motion machine (clears throat) no.

Superconducters release enough heat and absorb enough heat to burn of coolant, the electrons may magnetize for a long period but not indefinately.

A point I made completely overlooked.

As for the power generated, NYC being my example, these devices are used currently on destroyers, battleships, and aircraft carriers.

As for the technology being a pipe dream, the transport device in testing I described...

http://en.wikipedia.org/wiki/ET3_Global_Alliance

http://www.et3.com/

Sound familiar. Go argue it with Elon Musk, he's backing it.

[ZetaX]

A point I made completely overlooked.

So it can power NYC, yet you think some of that power could not be used to liquify some nitrogen¿ No, not overlooked, it's just obviously irrelevant.

As for the power generated, NYC being my example, these devices are used currently on destroyers, battleships, and aircraft carriers.

Evidence! You just keep on claiming the many uses yet completely fail to actually demonstrate one of them. You only link to several companies, but none of them back what you say.

[Rakaydos]

As for the power generated, NYC being my example, these devices are used currently on destroyers, battleships, and aircraft carriers.

Now we're getting somewhere.

Which classes/models of ship? Ship names? when playing to skeptics, you need to provide verifiable information.

(I suspect, when we track it down, it's all going to come to a mundane generator that uses superconductors, but relies on a different fuel source.)

Edited February 5, 2015 by Rakaydos

[pellinor]

As for the technology being a pipe dream, the transport device in testing I described...

http://en.wikipedia.org/wiki/ET3_Global_Alliance

http://www.et3.com/

I only find 'frictionless maglev' and that it consumes electric energy. A cool project, but no fundamentally new technology and no magical source of energy.

[GoSlash27]

There are no "currently used" battleships.

The last battleship ( USS New Jersey) was decommissioned nearly 15 years ago.

Best,

-Slashy

[LordFerret]

There are no "currently used" battleships.

The last battleship ( USS New Jersey) was decommissioned nearly 15 years ago.

Best,

-Slashy

Completely correct. My bad for throwing that in there.

[-Velocity-]

There are no "currently used" battleships.

The last battleship ( USS New Jersey) was decommissioned nearly 15 years ago.

Best,

-Slashy

Yea, that's what you think. But I know the truth- put on your tin foil hat so they don't wirelessly erase this knowledge from your head- they used a battleship to defeat an alien invasion a few years ago near Hawaii. They made a documentary from top secret footage Snowden leaked about it. I read about this on the internet, so it's true.

[Kryten]

LordFerret, your 'friend' is toying with you. He's feeding you complete BS, watching you swallow it, and laughing about it with his actual friends later.

[LordFerret]

LordFerret, your 'friend' is toying with you. He's feeding you complete BS, watching you swallow it, and laughing about it with his actual friends later.

My 'friend' is an uncle, who worked for IMG/GE on the 13 kilo-gauss magnets used in the first NMRIs... just one of the projects. Also was in and worked for the Navy (an applications hint). Doubt if you wish.

Also, GoSlash27, while the BB-61 (Iowa) and BB-62 (New Jersey) are indeed decommissioned, the guns on BB-62 are still operational. I don't know yet if it's to be the summer of 2015 or the summer of 2016, but a 'cleaning charge' (1/4 bag) will be fired from the 16-inchers of BB-62. Don't know the status or schedule for BB-61. The last cleaning charge fired from BB-62 wreaked havoc in nearby Philadelphia, shattering a number of windows. I plan to be there for the next one. I've been aboard BB-62, up close and personal, old salt radio engineers and restoration crew. Fun stuff.

[Kryten]

My 'friend' is an uncle, who worked for IMG/GE on the 13 kilo-gauss magnets used in the first NMRIs... just one of the projects. Also was in and worked for the Navy (an applications hint). Doubt if you wish.

Yes, of course, you have an uncle who worked on perpetual motions machines. Can any passing mods clarify if somebody can get banned for repeatedly and blatantly lying? LF, do you think anybody is impressed by this stream of complete nonsense?

[sal_vager]

This thread is a complete train wreck.

Closing.