Doubts on Energy.

[mos57]

As a boy I thought was a good observer of the world. I really liked physics because it allows me to understand many things that were happening around me using simple rules or laws.

So I'm aware of how important are the conservation laws. But my observations over time have matured doubt that one of them is incorrect or at least should be set differently.
So more than 25 years ago, I wrote a letter to Professor Antonino Zichichi at its research center in Erice (Sicily) to tell him about these issues, but I had never answer: perhaps the letter never came into his hands.

So now that I've seen is that many here are prepared in physics, perhaps you can finally take off the head of these evil thoughts.

I thank in advance all those who wish to participate in the discussion to clarify concepts and examples which I will discuss below.

Thanks much, Francesco.

 

[Wavebourn]

Bring concepts and examples in studio!

 

[SY]

So more than 25 years ago, I wrote a letter to Professor Antonino Zichichi at its research center in Erice (Sicily) to tell him about these issues, but I had never answer: perhaps the letter never came into his hands.

Physics professors get crank stuff all the time and rarely bother to read it or respond. There are two exceptions:

1. A particularly funny crank letter with innovative lunacy; these will get passed around for general amusement.

2. Letters that indicates an actual understanding of physics, correspondence with known laws (e.g., relativity reducing to Newton's laws at low velocities), explanatory power lacking in current thought, and a defined means of testing.

Anything else is likely to be chucked unanswered (or at best answered with a form letter).

 

[Gyuri]

I am brooding over it, which category my letter got into.

 

[mos57]

One day while walking I looked at the lights by the wayside as the ones you can see in Figure 1 and thought:

the pole that holds the lamp makes an effort or not?

The strength is there but there is no shift so then there is no work, so no energy. This is currently the beliefs of physics.

The lamps shown in Figure 2 have two light one right and one left.
Now substitute the two lamps with two buckets of water and replace it yourself at the stake center. Hold the two then dried for 8 hours and then go home.
I think you will tell your wife that you are very tired, because you've done a big job and when she asks you to tell her what you did.
But then she being an expert in physics tells you that you have not actually done any work and therefore it is absurd that feel so tired!!

What's wrong ??????

 

[Spasticteapot]

Force/time does not equal energy. Force/distance, however, does.

In the case of holding up the water with your arms, you're actually not expending any energy to hold it up. You are, however, expending a lot of energy to keep the muscles in your arms contracted. In this case, it's a large amount of chemical energy (food) being turned into a lot of heat.

 

[mos57]

Bring concepts and examples in studio!

there you are satisfied.

but you be careful: there may be other examples

 

[Wavebourn]

What's wrong ??????

Nothing.

Have you ever heard of tiredness of metal springs? It is a technical term. At least, in Russia, in "Resistance of Materials" course compulsory for almost all engineers.

 

[mos57]

Nothing.

Have you ever heard of tiredness of metal springs? It is a technical term. At least, in Russia, in "Resistance of Materials" course compulsory for almost all engineers.

Like springs in the cushions of my car?
In fact, now I have to replace it.

 

[Wavebourn]

Like springs in the cushions of my car?
In fact, now I have to replace it.

Ferrari?

I knew American tractors serve much longer. They are regenerative.

 

[cbdb]

How much work does a table or floor with something on it do?

None.

 

[Wavebourn]

How much work does a table or floor with something on it do?

None.

Think about molecules, atoms, elementary particles... Have you seen bottles of vintage vine, are they absolutely round as new?

 

[mos57]

How much work does a table or floor with something on it do?

None.

This is what we think just when we think of tables, bridges, skyscrapers (including support themselves), we say do not do any work.

But when the same things (weights) we will keep us humans then we realize that there is something different
Our experience tells us that there is a difference between keeping 30 kg on the head and not keep anything. But for the current physics between these two conditions, energetically does not change anything!!

We make an effort against gravity?

 

[mos57]

Who will give me the most convincing answer, I'll give these two fine (and round) bottles of wine directly to his house.

Francesco

 

[DF96]

Instead of human muscles, think of a lamp (or anything else) being held up by an electromagnet. The current through the windings generates a magnetic field which supports the lamp. To keep the current going we need to use some power. Does the power support the lamp? No, it just heats up the winding. We know that no work is being done on the lamp because it is not moving (kinetic energy) to a higher place (gravitational potential energy) or getting hotter (thermal energy) - its energy stays exactly the same.

So all the power needed is lost in heating the electromagnet, plus whatever power is lost in the inefficiency of the power supply (and the electricity grid/generator/boiler etc.). If we were really clever, we could use some of the heat from the electromagnet to make some more electricity so our total efficiency would improve. We would never get to 100%. This is why lamps are supported by lampstands and not electromagnets!

 

[mos57]

That's you think that when we support a lamp or a weight the energy consumed is just exactly the energy we dissipate into heat? (I must measure my temp when working)!!!

About electromagnet, you can also think of a circuit without heat loss, ie a superconducting ring or at least to a simply permanent magnet: either keep the lamp for a long time.
But both in the past must have been excited, giving them energy. The question is understand that this given energy then is exactly the same as the one returned.

 

[DF96]

Yes, if you use a perfect superconducting electromagnet then you put energy in at first to start the current. The energy is stored in the magnetic field. You get it back, mainly as heat, when you quench the magnet.

You also use energy to cool the magnet, but you just move this heat energy to somewhere else so probably lose it.

A permanent magnet is a bit different, because the magnetism is intrinsic from the spin of electrons. You need to put energy in to line them up the same way. It always costs energy to reduce entropy.

 

[mos57]

Yes, if you use a perfect superconducting electromagnet then you put energy in at first to start the current. The energy is stored in the magnetic field. You get it back, mainly as heat, when you quench the magnet.

What I try to tell you are in the between the start and the end of this cycle, when it is already magnetized, it may take another job. If there are non other losses, the energy of magnetization during demagnetization is returned (this last I not have tested, but it should be so), as even you say.
But when it is in the active phase of magnetization, electromagnet can lift a piece of iron. This is a further work, without spending more energy elsewhere.
Please let me know if i am wrong.

In the following I want to take another example or proof of what I want to tell:
Nowdays it is known that astronauts while are in weightlessness for a long time, then they lose muscle mass and tone overall. Isn't this a proof that on the earth there is more trouble or effort compared to an environment like empty space?
Does from this follows that one guy spends more energy to stay on earth proportionally to its gravity?

 

[SY]

Please let me know if i am wrong.

You are wrong. You are confusing the very different concepts of force, work, energy, and power.

 

[Sangram]

The difference is between the human being and the lightpole.

The lightpole is a rigid structure which is coupled to the very same point from which the force of gravity originates (or close enough).

The holding of a bucket of water is an active movement (though it does not appear to be) because energy is being expended in the muscles that hold up water (as there are free joints within the arm and muscles that are countering an opposing force).

The difference, in my amateur way of describing physics, is 'intended motion'. The pole has no possibility of moving downward hence it is not using any energy (at least not in ideal sense, however there is small amount of kinetic energy generated by small movement which is transmitted through the pole or converted to small amount of heat).

I have a friend with DMD, who is now bedridden and on ventilator. At one stage he lost control over his leg muscles and would keep falling down. We do actively counter the force of gravity with our bodies, if that's what you're hinting at. But holding two buckets of water off the ground is a lot more work than standing up as there is a downward force exerted on them.

To exaggerate your example, think of two loaded trucks hanging off the pole instead of water. Things will change rapidly