Where does a magnet get its energy?

Surely Gravity is always there.... it doesn't switch off when you're not exerting a force against it, so if you suspend a piece of steel from a magnet, acording to your thesis, the magnet will run out of energy and drop the steel as the constant pull of gravity will "drain" the magnet of energy.

By the same token the magnets in your electric motors would just run-out. Neither event I see happening. So unless it takes zillions of joules of energy to create a magnet and it then releases this energy very very slowly over many years of suspending a weight or spinning the electric motor, I wonder does the magnet defy the laws of physics and give more energy than it recieves.

Originally posted by Anonymous ATS
Surely Gravity is always there.... it doesn't switch off when you're not exerting a force against it, so if you suspend a piece of steel from a magnet, acording to your thesis, the magnet will run out of energy and drop the steel as the constant pull of gravity will "drain" the magnet of energy.

In theory that should happen but since scientist have been largely unwilling to acknowledge that energy does not seem to be conserved in such a process ( or at least expose the fact that there is a dimension/plane/whatever where energy may be flowing from) they came up with the stop gap measure of simply saying that magnets do no work. That fools the vast majority of lay people but obviously they can't believe it ( unless their properly indoctrinated i suppose) and just do it for the sake of maintaining credibility.

By the same token the magnets in your electric motors would just run-out. Neither event I see happening.

Well it's funny that you should mention how magnets in generators never need replacement and yet we have to listen to all these claims that permanent magnets are not really permanent... What i always want to ask is if that isn't permanent enough!

So unless it takes zillions of joules of energy to create a magnet and it then releases this energy very very slowly over many years of suspending a weight or spinning the electric motor, I wonder does the magnet defy the laws of physics and give more energy than it recieves.

Nothing can defy objective accurate laws of physics and if something seems to be 'defying' a current law that just means the law is inaccurate or incomplete. The following reference does in my opinion sum up why a a massive transfer of energy is just not required to create a permanent magnet:

Placing a steel bar in a magnetic field, then heating it to a high temperature and then finally hammering it as it cools. This can be done by laying the magnet in a North-South direction in the Earth's magnetic field. In this case, the magnet is not very strong but the effect is permanent.

en.wikipedia.org...

I don't like quoting wiki stuff on such 'highly' scientific questions but i think that is a generally accepted 'fact'?

Since a magnet is just a dipole, and all the supplied 'electricy' to a generator does is separate the charges thus creating a dipole, it really begs the question why dipoles are so apparently cardinal when it comes to electricity generation/tapping...

Stellar

Originally posted by StellarX

It is a property of something ... and yes, the molecules actually do drift out of alignment so that magnetism does decay over time.

How long exactly? It's always interesting how people claim this while calling those magnets 'permanent'. When one inquires as to the time scale and all the factors involved in this 'decay' you tend to get silence...

You can always read up on physics and see that temperatures and external magnetic fields may affect magnets. It's not silence but your refusal to do homework.






[edit on 8-7-2008 by buddhasystem]

OK for those of you who think magnets do work:

I stick a 50g magnet to a fridge door - how much work is it doing?

I now leave the same magnet lying on the floor - how much work is it doing?

Lastly, I leave the magnet stuck on top of the fridge, 1m in height, how much work is it doing now?

reply to post by StellarX


mm here we go again....some basic physics here ,no mention of mystical forces..www.coolmagnetman.com...

en.wikipedia.org...'s_equations

[edit on 8-7-2008 by gambon]

Experiment for you ....Buy a magnet ,test how strong it,then beat repeatedly it with a hammer ,test again to see strength ,see what YOUR results are..

[edit on 8-7-2008 by gambon]

Originally posted by FatherLukeDuke
OK for those of you who think magnets do work:

I stick a 50g magnet to a fridge door - how much work is it doing?

I have no idea? How much energy would it take to keep a non magnetized piece piece of iron up there?

I now leave the same magnet lying on the floor - how much work is it doing?

Far less than it would be doing while sitting against the side of a fridge...

Lastly, I leave the magnet stuck on top of the fridge, 1m in height, how much work is it doing now?

Do you not at all understand the difference between the examples?

Originally posted by buddhasystem
You can always read up on physics and see that temperatures and external magnetic fields may affect magnets. It's not silence but your refusal to do homework.

I am quite well aware of the effect of high or low temperatures on magnetized materials so please keep your patronizing tone to yourself. Why is that i have to be stupid and completely uniformed when i don't have to presume the same for you? Again please specify the differences between the three types of presumed systems wherein the thermodynamic system ( any part of the universe) in question can be investigated.

Stellar

Originally posted by gambon
mm here we go again....some basic physics here ,no mention of mystical forces..www.coolmagnetman.com...

en.wikipedia.org...'s_equations

I am familiar with what magnets can and can't do and while i don't claim to understand Maxwell's math i can discuss some of the conclusions he arrived at.

Experiment for you ....Buy a magnet ,test how strong it,then beat repeatedly it with a hammer ,test again to see strength ,see what YOUR results are..

I know what the results are because it's widely known. What happens when you hit a generator with a hammer while it's in operation? Don't you think that same general result will be obtained when you disturb the functioning of a specific system?

Stellar

Here's a good analogy for some of you to better understand magnets.


A magnet (natural magnet) is like a bi-directional spring. Yes, think of a physical spring.

The field around the magnet is like the coil of that spring.

The spring doesn't have any energy itself... but it stores force.
As you apply force to that spring, the spring pushes back. As you stretch the spring, the spring tries to recoil.

It's not a perfect analogy, nothing ever is (so don't start picking on me as if I were your professor).


The odd thing about magnets is it can work that force backwards. But it is by no means a self generated force, the energy always comes from another source.
Of course, then you get the laymen involved, and they will always swear there's something mystical about magnets because its a physical influence they cant see. But nobody can see magnetic fields, so I guess they will always be kind of mystified until they are educated.

Originally posted by johnsky
Here's a good analogy for some of you to better understand magnets.

A magnet (natural magnet) is like a bi-directional spring. Yes, think of a physical spring.

Does a spring perpetually emit electromagnetic radiation?

The field around the magnet is like the coil of that spring.

The spring doesn't have any energy itself... but it stores force.

The difference being that a magnet does have energy itself without anyone having to do anything to it?

As you apply force to that spring, the spring pushes back. As you stretch the spring, the spring tries to recoil.

Yes so work is being done with a resultant effect and that is not the mention the intelligently designed nature of the spring; this can hardly be said for a magnet.

It's not a perfect analogy, nothing ever is (so don't start picking on me as if I were your professor).

Your right, it's nowhere near a perfect analogy.

The odd thing about magnets is it can work that force backwards. But it is by no means a self generated force, the energy always comes from another source.

And that is my point? What energy source does a magnet/dipole tap to allow it to perpetually radiated away electromagnetic energy? If you are familiar with the workings of the common dipole you must at least understand that it's not at all understood how a dipole can do what it does and that is even more fascinating when one realises that all we ever do in our generators is separate charges so as to create dipoles!

Of course, then you get the laymen involved, and they will always swear there's something mystical about magnets because its a physical influence they cant see.

And i contend that your first mistake were to presume that i am your average lay person who opens a book once a year and starts making presumptions before having finishing the first page. Frankly i am disappointed with being presumed a common idiot so maybe we should start comparing what we have read in our lives thus far?

But nobody can see magnetic fields, so I guess they will always be kind of mystified until they are educated.

Well we can very much see magnetic fields by their effects and that has most certainly not cleared up the 'mystery' to the vast majority of those who work in this area of engineering/science.

Stellar

[edit on 11-7-2008 by StellarX]

Originally posted by Byrd
Remove the water molecules and the frog won't levitate.

Actually the same guys who were levitating the frog, were levitating plastics.

@StellarX

You can't convince people who have everything figured out, and have their mind made up. Its funny how people spout these analogies which is what is preventing them from understanding it in the first place.

reply to post by Freezer

Is it a plastic frog then?

Originally posted by StellarX

Originally posted by FatherLukeDuke
OK for those of you who think magnets do work:

I stick a 50g magnet to a fridge door - how much work is it doing?

I have no idea? How much energy would it take to keep a non magnetized piece piece of iron up there?

I now leave the same magnet lying on the floor - how much work is it doing?

Far less than it would be doing while sitting against the side of a fridge...

There isn't any work. Without movement there is no work. Magnets do not produce energy.

energy required to move an object in a force field = work
work = force x movement
power = work per unit of time = force x speed

Separating a magnet from the fridge requires energy. Leaving it where it is requires zero energy.

Originally posted by nablator
reply to post by Freezer

 

Is it a plastic frog then?

Sorry couldn't resist. Both water and plastic are diamagnetic.

Originally posted by nablator
Sorry couldn't resist. Both water and plastic are diamagnetic.

Well its said that all material except magnetic is diamagnetic to a degree.

Originally posted by nablator
There isn't any work. Without movement there is no work. Magnets do not produce energy.

energy required to move an object in a force field = work
work = force x movement
power = work per unit of time = force x speed

We see that makes sense through a formula. Lets say I ask you to hold a 5 pound weight for 5 minutes. It won't move while its in your hand. Does it not take work to maintain the weight in that position, or does it magically float there?


With magnets -
www.youtube.com...

Without magnets -
www.youtube.com...

Why did the ball roll further with the magnets installed? Glitch?

The work expended by humans holding something up is only on account of peculiarities of physiology, that you have to expend energy to keep muscles taut.

If you put something on an inert metal table, it does not take any work to keep it there.

mbkennel

The work expended by humans holding something up is only on account of peculiarities of physiology, that you have to expend energy to keep muscles taut.

And thus a exchange of energy between systems.

If you put something on an inert metal table, it does not take any work to keep it there.

I am not certain how this applies to a magnet against the side of a fridge. How can it be said that there is no exchange of energy between those systems?

Originally posted by nablator
There isn't any work. Without movement there is no work. Magnets do not produce energy.

Since when is work ( thermodynamical) related to movement?As far as i know work is in fact just energy transfer between thermodynamic systems?

energy required to move an object in a force field = work
work = force x movement
power = work per unit of time = force x speed

As i said above that is not a accurate description of work.

Separating a magnet from the fridge requires energy. Leaving it where it is requires zero energy.

In fact leaving a magnet against the side of a fridge does not result in work being done between you and the magnet but since there is very certainly work being done between the fridge and the magnet i still require a answer.

Stellar



[edit on 13-7-2008 by StellarX]

Originally posted by mbkennel
If you put something on an inert metal table, it does not take any work to keep it there.

That might make sense if there wasn't a thing called gravity. By your mode of thinking we shouldn't even need the table to suspend the object..Does earths gravity not pull comets into its vicinity by gravity? Does it take no energy to do that? I guess if you were to take the table out from under the object, the object would just stay there, because in order for it to move, work needs to be done, and gravity doesn't do work.

I guess you can't explain why the ball moves further with the magnets installed, because that doesn't makes sense from a physics standpoint. Must be a hoax cause it can't be scientifically explained, and we all know science can explain everything ever, and is never wrong, and can't be changed.

Originally posted by StellarX
Since when is work ( thermodynamical) related to movement? As far as i know work is in fact just energy transfer between thermodynamic systems?

We were talking about a mechanical system. Thermodynamic work is perfectly compatible with mechanical work. They are not different.

Joule contended that motion and heat were mutually interchangeable and that in every case, a given amount of work would generate the same amount of heat.

Mechanical equivalent of heat

Originally posted by Freezer
That might make sense if there wasn't a thing called gravity. By your mode of thinking we shouldn't even need the table to suspend the object..Does earths gravity not pull comets into its vicinity by gravity? Does it take no energy to do that?

Who said there is no energy? Where do hydroelectric power plants (dams) get their energy? Gravity.

I guess if you were to take the table out from under the object, the object would just stay there, because in order for it to move, work needs to be done, and gravity doesn't do work.

Weight is not the only force applied to the object on the table. Sum of all forces = zero. When you remove the table weight is the only force.

When an object gains kinetic energy (heat IS kinetic energy) the increment is equal to the work of the forces he is submitted to. This is a consequence of Newton's second law of motion:

F = mdV/dt (Newton's 2nd law)
V = dM/dt (speed)
dW = F.dM (definition of elementary mechanical work)
K = ½mV² (definition of kinetic energy)

dK = mV.dV = mdM.dV/dt = F.dM = dW

Originally posted by nablator
Who said there is no energy? Where do hydroelectric power plants (dams) get their energy? Gravity.

Thanks, thats all I wanted to hear. We can convert energy from gravity.

Now, explain why in the video the ball rolls further with the magnet installed.