Mass = Kinetic Energy

[Lowemack]

If Mass increases with velocity, is this due to the mass of the additional kinetic energy it possess.

 

If so does this mean that the rest mass of an object is just the sum of the Kinetic energy of its sub-atomic particles. i.e. the mass of a water molecule is the sum of the kinetic energy of all the quarks and electrons in the molecule.

 

Is this where the energy comes from when we burn hydrogen? a water molecule has less kinetic energy than 2 x Hydrogen and 1 Oxygen atom.

[Rasori]

I'm not sure, but I was under the impression that mass decreases with velocity.

 

Energy=Mass*Velocity^2. As velocity goes up, mass has to go down to keep the equation true.

[Lowemack]

I'm not sure' date=' but I was under the impression that mass decreases with velocity.

 

Energy=Mass*Velocity^2. As velocity goes up, mass has to go down to keep the equation true.[/quote']

 

That Formula is E=MC^2 and C is a suposed to be a "constant" (see other thread "New Theory?") and it doesn't go up.

[swansont]

E² = (mc²)² + (pc)²

 

where m in this equation is the rest mass (invariant). the kinetic term is separate

 

the notion that mass changes with KE comes from using E = mc² and saying that the mass is the total mass of the system, aka relativistic mass. You can do it, but you have to be careful what you mean by mass. Because of the confusion that is causes, it's not generally used.

 

Bound systems have less energy than free systems, and do have a mass difference. For nuclear reactions this is small. For chemical reactions, this is very, very small. But c² is big.

[Lowemack]

All I'm trying to ask is, "What is Mass?".

 

As mass increases relative to velocity, due to kinetic energy increases, could it be that "rest mass" is just a product of molecular kinetic energy.

[J.C.MacSwell]

All I'm trying to ask is' date=' "What is Mass?".

 

As mass increases relative to velocity, due to kinetic energy increases, could it be that "rest mass" is [b']just a product of molecular kinetic energy[/b].

 

Not "just" but in part, the way I perceive it (which is probably wrong).

 

To be more precise (read wrong again) I see it as the rest mass of the object but not of the molecule.

[mezarashi]

Hmm, I'm not sure how the discussion is going here, but to answer you're very first post, I think you are confusing classical mechanics with relativity and such. The only reason that mass increases when you approach high velocities is because the velocity (v) cannot exceed the speed of light ©.

 

So E = 1/2(mv^2)

 

If you E increases, that is you give it more energy by whatever means you'd like, there is no way that v will increase any further. The only way to balance the equation out then is to increase the mass (m). The relationships between how much the mass increases for any given velocity can probably be found from the Lorentz equations? as I seriously don't have them off the top of my head for now.

 

I don't think it has to do with what you were supposing up. Though the question of "what is mass" is another interesting one, but that itself can bet tackled by many many different perspectives, and I don't think its directly relevant to the original post. Anyway, did that answer your question?

[Martin]

this is an intelligent question. Frank Wilczek who just got the nobel prize for physics posted his acceptance lecture today and in it he explained in non-specialist terms how about 90 percent of the mass of a proton is the kinetic energy of the quarks buzzing around inside it.

 

the quarks do not have much rest mass, the proton has more rest mass than the sum of the quarks, therefore the difference is made up by all the commotion going on inside the proton, of its rapidly moving pieces. this is what you were saying

 

If Mass increases with velocity' date=' is this due to the mass of the additional kinetic energy it possess.

 

If so does this mean that the rest mass of an object is just the sum of the Kinetic energy of its sub-atomic particles. i.e. the mass of a water molecule is the sum of the kinetic energy of all the quarks and electrons in the molecule.

....[/quote']

 

However the mass of a molecule is NOT significantly due to the motion of the ATOMS because in most molecules the atoms do not move around fast enough to contribute much.

 

...

 

Is this where the energy comes from when we burn hydrogen? a water molecule has less kinetic energy than 2 x Hydrogen and 1 Oxygen atom.

 

NO that is NOT true, the energy released is mostly POTENTIAL energy because atoms that want to get together have gotten closer together and those that are not too attracted to each other have come apart.

 

the two oxygens in the O2 molecule are weakly joined and when they find two hydrogen molecules H2 and H2 they split apart and fall into the arms of them and become tightly joined and so it is the FALLING TOGETHER into better combinations that releases the energy.

 

there is only some temporary kinetic energy (as heat) in chemical reactions but then it is not enough to worry about.

 

but you are right about the QUARKS inside the proton

[Lowemack]

But what if the rest mass of a Quark was due to the kinetic energy of IT'S yet unknown constitutional parts.

 

We keep saying, "..the mass of its kinetic energy..".

 

It sounds strange saying that Kinetic energy has mass, but what if thats just what mass is - Kinetic Energy? Totaly interchangable with the formulae E=MC^2.

 

PS Thanks for the Potential energy info in Hydrogen burning calculations.