Philosophy Major Seeking Physics Answers

[renzagliarobb]

Your body consumes fuel in the form of food and oxygen. The byproducts of this, CO2 and other things, have LESS mass than they did before they were used. Some of this energy is converted into heat, which is why you heat up and sweat when you exercise. Some of that energy goes into the actual moving of your muscles and is expended that way.

Now the key here is that when you BREAK something you have broken the bonds of the atoms and molecules that make up that object. After you broke them they did not reform and bind with something else like the fuel in your body does. If I break a piece of wood in half and then throw it into the fire, the wood burns and releases energy. If you could measure every particle from that wood before and after the fire you would find that it has less mass than they did before.

Also, remember that energy can be converted to light as well. That is why a fire is visible.

Edit: When I say "Energy is Expended" I mean that it is converted to another form and cannot be used for further work. NOT that it simply dissapears.

This is all true. I thought the premise of the conversation was the conversion of energy from work done (from the body) to the mass of an object.My question... "how does the mass of an object "increase" from the breaking or unbinding of these molecules"? If energy from our body is converted to mass in the object...how is this done?

The questions you have answered were purely rhetorical. I think we have swayed from the premise of the question.

 

[Drakkith]

This is all true. I thought the premise of the conversation was the conversion of energy from work done (from the body) to the mass of an object.My question... "how does the mass of an object "increase" from the breaking or unbinding of these molecules"? If energy from our body is converted to mass in the object...how is this done?

The questions you have answered were purely rhetorical. I think we have swayed from the premise of the question.

The force applied to the object to break the bonds supplies the energy that is converted to extra mass.

 

[renzagliarobb]

The force applied to the object to break the bonds supplies the energy that is converted to extra mass.

But how?

 

[i_drank_what?]

So it sounds like you can break a piece of wood, in which case the sum of the mass of the two parts will exceed the mass of the original piece, or burn it in which case the mass of the sum of the parts will be less than the original whole, but there is no way to destroy the piece of wood (or anything) without either converting some mass to energy or vice versa.

Is this correct?

Thanks again everyone, I know philosophy and physics don't exactly go hand-in-hand, and it was difficult to phrase the question without explaining the theory in whole (which I promise you would have bored you to tears) but I appreciate how helpful and enthusiastic this community has been...really...you people are repairing the internet's reputation post-by-post.

 

[Drakkith]

But how?

The act of breaking or making chemical or nuclear bonds uses or releases energy. When you add or remove energy from something you increase or decrease its mass.

 

[renzagliarobb]

So it sounds like you can break a piece of wood, in which case the sum of the mass of the two parts will exceed the mass of the original piece, or burn it in which case the mass of the sum of the parts will be less than the original whole, but there is no way to destroy the piece of wood (or anything) without either converting some mass to energy or vice versa.

Is this correct?

Thanks again everyone, I know philosophy and physics don't exactly go hand-in-hand, and it was difficult to phrase the question without explaining the theory in whole (which I promise you would have bored you to tears) but I appreciate how helpful and enthusiastic this community has been...really...you people are repairing the internet's reputation post-by-post.

Yes what "you said" is correct.. I do not understand your reasoning of "how mass is added". I only see talking around "how you would add mass to an object's mass if you break it with you body's energy", how does body energy convert to an object's mass?Mass is converted to energy easier than energy converts to mass.

 

[renzagliarobb]

The current way I've seen nuclear fission and fusion described is that the reactions liberate energy and the resulting particles have less mass than the originals.

However, I have recently heard that mass itself doesn't go away or change. (Rest mass)
So unfortunently I actually don't know.

Not with fussion. Here energy is lost as the atoms fuse together but the combined mass from fusion is actually larger. the atoms don't have as much combined weight, but the atoms fuse and have more mass, don't they? I believe this is why the popular way to convert nuclear power in usefull energy (like at a NPP) is through fission. Fission involve taking something and making it smaller by taking the energy out of the mass. Where do you ever hear of converting nuclear power using fusion?

 

[renzagliarobb]

If you bend plastic back and forth until it breaks, you heat it up. You might consider this added energy added gravitational mass, but you aren't increasing the rest mass at all...

The added energy comes from a chemical reaction in the plastic and this energy is released from the plastic itself...so the mass decreases.

 

[renzagliarobb]

Well you are adding energy, but it is so small that touching the object will add/remove mass by a few orders of magnitude more than what you changed by breaking the object , so this isn't really a good question.

I agree.

 

[renzagliarobb]

First of all, thank you all for your timely and helpful responses,

Perhaps a better question might be "is it theoretically possible that all of the mass be preserved in the process of breaking the wood, while in the same sense impossible for the products of splitting an atom to have the same cumulative mass as the original atom," I guess I am asking if this is a fundamental difference between atoms and other objects.

I want to make an argument along the lines of "you can destroy a boat without destroying any mass, but you cannot destroy an atom without destroying any mass"

Yes, I wouldn't say destroying the mass though...I would say it decreases the mass as the mass is converted to energy. Nothing is ever really destroyed. :)

 

[renzagliarobb]

So it sounds like you can break a piece of wood, in which case the sum of the mass of the two parts will exceed the mass of the original piece, or burn it in which case the mass of the sum of the parts will be less than the original whole, but there is no way to destroy the piece of wood (or anything) without either converting some mass to energy or vice versa.

Is this correct?.

Thanks again everyone, I know philosophy and physics don't exactly go hand-in-hand, and it was difficult to phrase the question without explaining the theory in whole (which I promise you would have bored you to tears) but I appreciate how helpful and enthusiastic this community has been...really...you people are repairing the internet's reputation post-by-post.

 

[renzagliarobb]

No, parts will not excede their original mass after breaking them...their combined mass will decrease.

 

[renzagliarobb]

Wouldn't the mass be slightly LOWER after breaking the chemical bonds, since you liberated energy stored in them?

Yes.

 

[Drakkith]

Not with fussion. Here energy is lost as the atoms fuse together but the combined mass from fusion is actually larger. the atoms don't have as much combined weight, but the atoms fuse and have more mass, don't they? I believe this is why the popular way to convert nuclear power in usefull energy (like at a NPP) is through fission. Fission involve taking something and making it smaller by taking the energy out of the mass. Where do you ever hear of converting nuclear power using fusion?

Incorrect. When you fuse 2 light nuclei together, their combined mass is LESS than their individual masses were before they were combined. On the opposite end, when you split a heavy nucleus the mass of its products are less than the original nucleus. In both cases you have liberated energy. This removal of energy means that the mass has decreased.

Originally Posted by Lsos View Post

Wouldn't the mass be slightly LOWER after breaking the chemical bonds, since you liberated energy stored in them?

Yes.

The mass would only be lower if breaking the bonds released more energy than it took to break them in the first place. Think of a fire. In a fire oxygen from the atmosphere reacts with carbon in the fuel and forms CO2. In the process it gives off energy in the form of heat and light. In this case the mass of the CO2 is LESS than the mass of the individual Oxygen and Carbon atoms before they combusted.

Now look at water. Water is composed of 2 hydrogen atoms bound to 1 Oxygen atom. H2O. By electrolysis we can split the hydrogen from the oxygen. But guess what. This TAKES energy to accomplish and releases NONE. Now the oxygen and hydrogen atoms have a combines mass that is MORE than the water molecule that they came from.

If you remove energy from something the mass will decrease, and when you add energy it will increase.

 

[renzagliarobb]

Incorrect. When you fuse 2 light nuclei together, their combined mass is LESS than their individual masses were before they were combined. On the opposite end, when you split a heavy nucleus the mass of its products are less than the original nucleus. In both cases you have liberated energy. This removal of energy means that the mass has decreased.



The mass would only be lower if breaking the bonds released more energy than it took to break them in the first place. Think of a fire. In a fire oxygen from the atmosphere reacts with carbon in the fuel and forms CO2. In the process it gives off energy in the form of heat and light. In this case the mass of the CO2 is LESS than the mass of the individual Oxygen and Carbon atoms before they combusted.

Now look at water. Water is composed of 2 hydrogen atoms bound to 1 Oxygen atom. H2O. By electrolysis we can split the hydrogen from the oxygen. But guess what. This TAKES energy to accomplish and releases NONE. Now the oxygen and hydrogen atoms have a combines mass that is MORE than the water molecule that they came from.

If you remove energy from something the mass will decrease, and when you add energy it will increase.

The combined mass! What grade are you in?

 

[V_K]

for quantum world and macroworld you will have quite different answers.
In general you can not break something without damage to structure. You have to apply a force to break something, and you spend energy for that. You always change the energy state by rendering a force.

 

[Drakkith]

The combined mass! What grade are you in?

Umm, what?

 

[Buckleymanor]

Not with fussion. Here energy is lost as the atoms fuse together but the combined mass from fusion is actually larger. the atoms don't have as much combined weight, but the atoms fuse and have more mass, don't they? I believe this is why the popular way to convert nuclear power in usefull energy (like at a NPP) is through fission. Fission involve taking something and making it smaller by taking the energy out of the mass. Where do you ever hear of converting nuclear power using fusion?

An object can't have less weight but more mass.The density can change it might be larger in size but that is not the same as something having more mass.

 

[Physicist1231]

If you toss the string theory into the mix stating that Mass is nothing more than condensed energy you can state that if you break an object (in any manner) what ever mass/energy is released still remains intact just in a different form. Thus adding the physical remaining mass and energy released (since they are the same according to the string theory) then the overall mass will not change.

 

[MayMonth]

Please forgive me for being so ignorant but I hope you guys would be willing to answer this (stupid) question of mine. Breaking of chemical bonds was mentioned here, but is any chemical bond broken when you break a piece of wood? It's still 'wood' before and after, not like it has been changed to some other compound or element. So I still don't quite understand how the final mass will exceed the initial. Please enlighten me on this.

Thanks!

 

[Drakkith]

Please forgive me for being so ignorant but I hope you guys would be willing to answer this (stupid) question of mine. Breaking of chemical bonds was mentioned here, but is any chemical bond broken when you break a piece of wood? It's still 'wood' before and after, not like it has been changed to some other compound or element. So I still don't quite understand how the final mass will exceed the initial. Please enlighten me on this.

Thanks!

The wood is held together by bonds between the molecules. They aren't as strong as say the bond between a Hydrogen atom and an Oxygen atom in Water, but breaking anything still requires breaking of these bonds.

 

[ASD16]

if u are considering each and every molecule of the wood then yes...the mass will be same...wherther it is in air or wherever...the mass will remain constant...its only in chemical reactions that mass discrepancy come up becoz of mass converting into energy and vice versa...but in any physical change like breaking into pieces etc...the mass will remain unchanged...

 

[Drakkith]

if u are considering each and every molecule of the wood then yes...the mass will be same...wherther it is in air or wherever...the mass will remain constant...its only in chemical reactions that mass discrepancy come up becoz of mass converting into energy and vice versa...but in any physical change like breaking into pieces etc...the mass will remain unchanged...

I don't think so. You are breaking bonds, which requires energy, so the mass will increase a minuscule amount.