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Posted
So let me ask you this, a bullet hit a block and imbeded. They move together after that. Determine the energy using the momentum, then energy method. Each method gives a different value. What value would you pick? Don't tell me it's two different thing. This case have only 1 answer. I'm waiting. The real experiment shows that 1 case is true, the other method is wrong. Tell me which case if you really know what you talking about. If that's the case, what's wrong with the other method? If it's too complicated, you don't have to do it. YOu can just answer me if energy can be calculated from both method, then why 1 wrong? You said this isn't a problem. It is a huge problem if you don't know which value to choose. This is your problem. You just say it's two differnt, unrelated quantity, then how the heck do 1 know what method to use when they have to pick? This is as logical as it can get.

 

So the basic gist of this is that you don't understand energy and momentum. Because the solution to this problem is regularly solved by physics 101 students. That you can't figure it out does not point out any flaw in physics.

Posted (edited)

bullet mass m,velocity v. block mass M, velocity V. Imbeded, moved together.

 

Energy method:

Initial energy

1/2 mv^2 + 1/2 MV^2 .

Final energy

1/2*Mtogether*(Vtogther)^2 + sound + imbeded energy

 

momentum method:

mv+MV=Mtogher(Vtogether)

Vtogether=(mv+MV)/Mtogether

final energy= 1/2 * Mtogether * Vtogether^2

 

Two different answer.

Which one is better man? Which one is right man? Or use both method? How do I combind both method to use man? So what man? Law of Energy conserve is flaw or law of momentum flaw man.

 

Oh and you may said the velocity in energy method must be lower. In reality, it moves at the velocity of the momentum case, so you have extra sound and imbedment energy. Don't bother ask me for proof, do the homework yourself.

Edited by absolute1
multiple post merged
Posted

...

what is "imbeded energy"? why do you have "sound" in your energy considerations?

Why does your "momentum method" end with "final energy" result? Momentum is NOT energy..

 

the burden of proof is on you, not on us, it's our RESPONSIBILITY to ask you for proof, because we're science-minded people.

 

If science wasn't vigorous about proof, our world would still be considered flat, the sun would still be revolving around it.

 

Own up to your responsibility. You're the one who decided to come to US, not the other way around.

 

Own up or stop wasting our time. When you registered there was a section about reading the rules (which you AGREED to, otherwise you'd not have been registerd). I suggest you also own up to the responsibility of READING the rules you signed up you supposedly are going to read, and save us all wasting valuable time.

 

~moo

Posted
bullet mass m,velocity v. block mass M, velocity V. Imbeded, moved together.

 

Energy method:

Initial energy

1/2 mv^2 + 1/2 MV^2 .

Final energy

1/2*Mtogether*(Vtogther)^2 + sound + imbeded energy

 

momentum method:

mv+MV=Mtogher(Vtogether)

Vtogether=(mv+MV)/Mtogether

final energy= 1/2 * Mtogether * Vtogether^2

 

Two different answer.

Which one is better man? Which one is right man? Or use both method? How do I combind both method to use man? So what man? Law of Energy conserve is flaw or law of momentum flaw man.

 

Oh and you may said the velocity in energy method must be lower. In reality, it moves at the velocity of the momentum case, so you have extra sound and imbedment energy. Don't bother ask me for proof, do the homework yourself.

 

You've made a simple mistake here.

 

the final momentum is not:

 

mv+MV=Mtogher(Vtogether)

 

But:

 

mv+MV=Mtogher(Vtogether) + P_airatoms and possibly another term from imbedding in the block.

 

These other terms are normally ignored but if you do that you ignore what you call "imbeded energy" and sound...

Posted

Please read Physics For Scientists and Engineers 4th edition by Serway, p. 244, the section called Elastic Collisions. This talks about how you have to use both the conservation of momentum and energy to solve problems when the collision isn't perfectly inelastic. In fact, on p. 246, there is a worked example of a bullet impacting a block.

Posted
bullet mass m,velocity v. block mass M, velocity V. Imbeded, moved together.

 

Energy method:

Initial energy

1/2 mv^2 + 1/2 MV^2 .

Final energy

1/2*Mtogether*(Vtogther)^2 + sound + imbeded energy

 

momentum method:

mv+MV=Mtogher(Vtogether)

Vtogether=(mv+MV)/Mtogether

final energy= 1/2 * Mtogether * Vtogether^2

 

Two different answer.

 

 

"final energy" in your momentum section is the "final kinetic energy"

 

kinetic energy is not a conserved quantity except under certain circumstances.

Posted

According to his other post, it seems he left the forum.

 

In case he didn't, I would also want to know why sound is in the equation, and ask you guys if by "imbeded energy" you mean "embedded" energy, and, if that, perhaps, means "internal" energy ? I am not sure I understand that energy consideration..?

 

~moo

Posted

I'd say imbeded energy is supposed to embedded energy, so the energy to break the structure of teh block for the bullet to go into it, which after the bond breaking will probably mostly be heat.... and sound because a bullet hitting a block is going to make a noise.

Posted
I'd say imbeded energy is supposed to embedded energy, so the energy to break the structure of teh block for the bullet to go into it, which after the bond breaking will probably mostly be heat.... and sound because a bullet hitting a block is going to make a noise.

 

Since when do we include sound in our energy considerations, regardless of whether or not it's produced, though? Am I missing something here..?? If anything, it should be air-friction (which, technically, would produce the sound), but that too isn't ENERGY, it's force.

 

We either calculate this using energy considerations (sound and friction should not be included) or using forces (which means that it's a projectile movement, with initial velocity, bla bla).

 

Or am I missing something..?

Posted

sound = waves = energy transport

 

So the sound waves will take energy away from the system.

 

If you're being rigorous you should include it... but most problems just ignore it.

Posted
sound = waves = energy transport

 

So the sound waves will take energy away from the system.

 

If you're being rigorous you should include it... but most problems just ignore it.

 

Wouldn't being rigorous also include substantiating the claims with a bit more than "woooo" "haaaa" and "yay", too?

 

I love it when being rigorous becomes a selective choice :P

 

~moo

Posted
Wouldn't being rigorous also include substantiating the claims with a bit more than "woooo" "haaaa" and "yay", too?

 

I love it when being rigorous becomes a selective choice :P

 

~moo

 

lol, yes it would :)

Posted

Hi all again,

 

Yeah, probably surprise to see me. I just want to apologize to you guys. I let myself way too excited for new finding. This is what I believe. Spiritual came to me and reveal to me the logic of nature. I feel go great about this logic that completely determine the ultimate answer by myself without listening to the spirit anymore. They left me... and as I continue to expand to the new finding, I can't find the logic necessary. Sigh... all is gone. So I only retain some truth to this logic. The last post was my theory on the view of mass. Of course that made up by me without further listening to what spririt have to say so it's imcomplete. But that's, the crack point to nature. We need different view to find the answer.

 

Back to this momentum problem. I can't complete convince you guys to believe me in this case because it involve so many parameter. Sound, heat, vibration, air. Even though it's a simple case, but internal it's not at all.

 

Recall an object M trave at V hit another object half of its mass at rest. Let's say it's complete momentum transfer. The Object M now at rest and object 1/2 M moving at 2V. So the kinetic energy 1/2M possess is twice the amount of M when it moving. We have a net gain in Kinetic energy. Now plug that energy back to move M, you'll get M to a higher V. As the process continue, you gain and gain energy. However, how can you convert kinetic energy into some other form of energy? 1 of them is potential. Which we will ignore. The other is electric. Now maybe you don't believe Behdini motor, but that's the process that it use. Kinetic energy excess gain from wheel to electric, electric back to wheel. I can perfectly prove the mechanism in gravity, but I will choose to be selfish this time for the purpose of financial.

Posted

I believe that all of our scientific grounding is standing on air. As much as i would like to praise the scientific community for their firm belief in the conquest of the ultimate truth(s) and the hard work being done to improve the materialist world , i believe that the very nature of our scientific movement, i.e, the firm belief in the validity of the rational and material, combined with a decision to ignore the irrational, validates my first statement. We believe in a lot of dogmas that have as much reason for being "true" as would flying saucers, the hindu scriptures, etc...I believe reason and logic are incomplete...the latter was proved by goedel and made worse by turing if i am correct... The existence of a void in rational thinking cannot be digested by naive scientists who would rather push it aside and advance in materialistic exploration since it has huge demand by society...A rapidly evolving human nature... I just wonder...how long can this go on? How many contradictions can we be aware of and live with at the same time? Any ideas/comments?

Posted
Hi all again,

 

Yeah, probably surprise to see me. I just want to apologize to you guys. I let myself way too excited for new finding. This is what I believe. Spiritual came to me and reveal to me the logic of nature. I feel go great about this logic that completely determine the ultimate answer by myself without listening to the spirit anymore. They left me... and as I continue to expand to the new finding, I can't find the logic necessary. Sigh... all is gone. So I only retain some truth to this logic. The last post was my theory on the view of mass. Of course that made up by me without further listening to what spririt have to say so it's imcomplete. But that's, the crack point to nature. We need different view to find the answer.

 

right.... ok...

 

Back to this momentum problem. I can't complete convince you guys to believe me in this case because it involve so many parameter. Sound, heat, vibration, air. Even though it's a simple case, but internal it's not at all.

 

Recall an object M trave at V hit another object half of its mass at rest. Let's say it's complete momentum transfer. The Object M now at rest and object 1/2 M moving at 2V. So the kinetic energy 1/2M possess is twice the amount of M when it moving. We have a net gain in Kinetic energy. Now plug that energy back to move M, you'll get M to a higher V. As the process continue, you gain and gain energy. However, how can you convert kinetic energy into some other form of energy? 1 of them is potential. Which we will ignore. The other is electric. Now maybe you don't believe Behdini motor, but that's the process that it use. Kinetic energy excess gain from wheel to electric, electric back to wheel. I can perfectly prove the mechanism in gravity, but I will choose to be selfish this time for the purpose of financial.

 

Let's take a moment to think...

 

[math]E= \frac 1 2 mv^2[/math]

[math]P=mv[/math]

therefore:

[math]E= \frac 1 2 \frac {P^2} {m}[/math]

 

That should help your confusion about missing energy and or momentum...

 

Now I can't quite understand what you then go on to talk about but I'll take a guess that it's a free energy device, which will NOT work in reality Bedini motors are not free energy devices at all, in any way. It's a con.

 

I believe that all of our scientific grounding is standing on air. As much as i would like to praise the scientific community for their firm belief in the conquest of the ultimate truth(s) and the hard work being done to improve the materialist world , i believe that the very nature of our scientific movement, i.e, the firm belief in the validity of the rational and material, combined with a decision to ignore the irrational, validates my first statement.

 

Science needs evidence without it, it's not science it's just junk. Science is all for the irrational if it is sound and has evidence, just look at quantum mechanics or relativity.

 

We believe in a lot of dogmas that have as much reason for being "true" as would flying saucers, the hindu scriptures, etc...I believe reason and logic are incomplete...the latter was proved by goedel and made worse by turing if i am correct... The existence of a void in rational thinking cannot be digested by naive scientists who would rather push it aside and advance in materialistic exploration since it has huge demand by society...A rapidly evolving human nature... I just wonder...how long can this go on? How many contradictions can we be aware of and live with at the same time? Any ideas/comments?

 

Contradictions like what?

Posted

Back to this momentum problem. I can't complete convince you guys to believe me in this case because it involve so many parameter. Sound, heat, vibration, air. Even though it's a simple case, but internal it's not at all.

 

Recall an object M trave at V hit another object half of its mass at rest. Let's say it's complete momentum transfer. The Object M now at rest and object 1/2 M moving at 2V. So the kinetic energy 1/2M possess is twice the amount of M when it moving.

 

You'll have a lot of trouble convincing people when you cite an example that does not happen. An object of mass M striking an object of mass m (M>m) will not come to rest after the collision.

 

Assuming that it does is the basis of your unphysical result. If you get a result that violates conservation of energy, you don't assume that conservation of energy is wrong, you assume the reaction does not take place. (unless this is an empirical result). A thought experiment cannot disprove the science — only nature can do that.

Posted

absolute1,

 

PLEASE find and read this reference I posted above. It talks about exactly the situation you are talking about -- inelastic collisions where you often have to use BOTH conservation of momentum and energy to solve problems. And, again, at the end of the section there is a completely worked out example involving a bullet impacting a block.

 

You can find this physics text at any university library (it is a very popular text for physics courses) and any library can get you a copy through Interlibrary Loan.

 

For that matter, almost any university level physics text will have a section on inelastic collisions. Please study that section and learn how to solve problems of these kind and then come back and see if you still think that there is something wrong with conservation of energy & momentum (which may be two of the most verified theories ever).

 

 

Please read Physics For Scientists and Engineers 4th edition by Serway, p. 244, the section called Elastic Collisions. This talks about how you have to use both the conservation of momentum and energy to solve problems when the collision isn't perfectly inelastic. In fact, on p. 246, there is a worked example of a bullet impacting a block.
Posted

Klaynos

 

Science bases itself on axioms/dogmas, which on a fundamental level become quite hard to imagine...For example fundamental concepts such as mass, charge, etc are concepts we cannot claim to have a solid understanding of. In mathematics, we make use of the concept of the infinite and the infinitesimal to describe many other concepts... It seems to work...it is something inconcievable but it works, and that's that.

My opinion about the quantum world, which someone stated works like magic, is similar, since after all, everything is described using abstract mathematical language. How can one claim to have understood quantum mechanics to any level, if the language used to describe it works inconceivably. This is also one of the contradictions we live with, and some of us accept it to be part of human limitation...

 

I also belive that there are a multitude of things which language cannot even begin to describe, since it does not give rise to an idea of unquestionable "evidence".

Any one who has had experiences with strong psychedelics would agree with me.

the path of Science is controlled by man,And the idea of science has its history placed in the advancement of man and material way back to the invention of written language especially in the western world. Material evidence is another dogma. This is another contradiction we live with, and some of us accept to be part of human limitation.

The fact that we use language to communicate ideas and "evidence", knowing that it is limited in its ability to describe the world around us,and that we are programmed to believe many things without experiencing the "evidence" is somewhat of a contradiction.

And this leads to massive abuse of language, causing the many attempts of describing "transcendental" experiences to sound corny and uninteresting. Many ancient writings sound corny and naive, which i believe is the result of the observer abusing the attempt of the language to describe something it cannot very well, and failing to find meaning is partly the fault of the observer for not being aware of this limitation and having strong faith in the ability of language.

Many more contradictions can be arrived at. Contradictions which reflect our basic individual nature on our collective behaviour. Society is full of contradictions. Anyone who has travelled to foreign lands will be aware of this reflection more easily than a person in his/her native place...i don't think anyone would want me to list out social contradictions.

These are my opinions.

Posted

LeThaX,

 

Much of your post, I think, falls under "argument from incredulity." That you have difficulty understanding aspects of science does not meant they are not understood by others.

 

And there are parts that would fall under "non-sequitur" because they have nothing to do with science.

Posted
LeThaX,

 

Much of your post, I think, falls under "argument from incredulity." That you have difficulty understanding aspects of science does not meant they are not understood by others.

 

\QUOTE]

 

My failure to share beliefs with a certain collective of thinkers, may lead you to think that I have difficulty understanding aspects of science. May be if you point out where my difficulties lie, I could contribute clearer ideas.

 

 

And there are parts that would fall under "non-sequitur" because they have nothing to do with science.

 

About the non-sequitur, i merely shared some of the ideas of the first post on this thread by abolute1....about "democratising" some areas of scientific movements...

I have merely produced speculations which may or maynot have anything to do with your science.

 

I think that the hardcore belief in cartesian, aristotelian, euclidean thinking has a far more adverse effect when it comes to the "completeness of science" which scientists are (also) trying to understand...

I am sorry swansont for i believe your inability to understand this brings you a false sense of comprehension...

My speculation holds no sure shot solutions though... I believe that completeness in understanding maybe possible. But to share it, communicate it through language will always suffer from incompleteness.

Posted
about "democratising" some areas of scientific movements...

 

science is not a democracy and can never be a democracy. it must remain a meritocracy for any progress to be made. new ideas need to have sort of fmerit to get anywhere because if they don't then they are just wrong and useless to science.

Posted

Science is not involved with just pulling ideas out of the air.

 

They are derived mathematically and shown experimentally.

Posted

Dogma is a belief or doctrine in something that is not to be disputed or doubted.

 

Science is generally "anti-dogma" as everything is to some extent disputed and doubted until shown otherwise.

 

What is true, is that certain results/theorems in theoretical and mathematical physics that are now "dogma" need to be re-examined from a modern perspective. It is quite possible that some results rely on assumptions/axioms etc that are no longer believed to be necessary/true/valid etc. This is particularly true of "no-go theorems".

Posted

I believe reason and logic are incomplete...

 

I might agree with this. The question is what your suggested action is? To me the utility of logic and reason is by no means contradicted by it's incompleteness or lack of perfection - on the contrary do I think that our awareness of the incompleteness may even improve our development. The point of "reasoning" to me isn't perfection, it's progress. If we had perfection, the reasoning would appear almost redundant to me.

 

Science bases itself on axioms/dogmas, which on a fundamental level become quite hard to imagine...

 

I wonder what you have in mind? Are you thinking of axiomatic formulation of certain scientific theories, or the scientific method?

 

In any case, I agree there is room for improvement here.

 

I also belive that there are a multitude of things which language cannot even begin to describe, since it does not give rise to an idea of unquestionable "evidence".

 

But I think the development of knowledge certainly go hand in hand with the development of language.

 

Look at mathematics and physics, that sometimes seems to have a symbiotic relationsship. With the right language saying what you want may be far easier.

 

Any one who has had experiences with strong psychedelics would agree with me.

 

Odd argument. Is this supposed in your favour? :P

 

These are my opinions.

 

Your "critics" of science, makes me wonder what you suggest instead.

 

Some of your question might fit within philosophical and foundational reflections of science and it's methods, but the outcome of such discussions should be a constructive improvement and not just a plain rejection.

 

The question of what is evidence, and what is sufficient evidence is old questions of philosophy of science. I think asking them is good, if done in a constructive spirit.

 

Like ajb said, I don't think a serious scientifically minded person is favoured of beeing dogmatic. Anyway, the scientific method as I personally see it, is no more static than the knowledge it produces. Anyone seriously applying a method for some utility, should be interesting in improving the former too.

 

A constructive questioning of the scientific method IMO, is one which reasons and suggest improvements.

 

I couldn't tell if you have some serious suggestions in mind, or if you rather favour some "religious style" road?

 

/Fredrik

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