The mass-energy tag has no wiki summary.
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Higgs Boson mass in Electron volts?
Im no physics genius here, I was just interested in the Higgs Boson so I was reading this article : How the Discovery of the Higgs Boson Could Break Physics
I came across this
Furthermore, ...
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1answer
558 views
Does the mass of a battery's change when charged/discharged?
... and if so, how much? Is it possible to detect it, or is it beyond any measurement? I'd say there are two possible scenarios (depending on the battery type) and both seem interesting:
The battery ...
10
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2answers
283 views
How does rest mass become energy?
I know that there's a difference between relativistic rest mass. Relativistic mass is "acquired" when an object is moving at speeds comparable to the speed of light.Rest mass is the inherent mass that ...
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4answers
368 views
What matter in the original atom bomb is converted to energy?
When an atom bomb goes off some matter is converted to energy according to $E = m c^2$.
I'd like to know exactly what matter in the original atom bomb is converted to energy. Is it protons, neutrons, ...
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4answers
349 views
How does $E=mc^2$ put an upper limit to velocity of a body?
How does $E=mc^2$ put a upper limit to velocity of a body? I have read some articles on speed of light and they just tell me that it is the maximum velocity that can be acquired by any particle. How ...
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4answers
225 views
Can you create mass with $E=mc^2$?
If you use the equation $E=mc^2$ could you make matter by dividing the $c^2$? I'm sorry if this is a really stupid sounding question or if it shouldn't be asked here.
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4answers
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What was Albert Einstein's proof for $E=mc^2$?
Most people know the famous equation:
$$E=mc^2$$
What were his steps of thinking for this equation that helped us discover so much about our world?
5
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1answer
393 views
Mass converted to energy in a common fire?
In a common wood fire such as a campfire, is matter converted to energy or is it simply an exothermic chemical reaction and all the mass can be accounted for in the ash and soot?
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3answers
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What's the purpose of the arbitary additive constants in Einstein's Inertia of Energy Paper?
In Einstein's paper: Does the Inertia of a Body Depend upon its Energy content? he introduces arbitary additive constants whose purpose I'm confused about.
The paper has a frame $(x,y,z)$ where a ...
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2answers
336 views
Does the mass of a body absorbing photons increase?
Let's say I have a photon collector in orbit around the sun. It manages to collect photons perfectly efficiently, that is, without radiating off any energy.
Then, using Einstein's equation:
$$E = m ...
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1answer
939 views
How to explain $E=mc^2$ mass defect in fission/fusion
What is the nature of nuclear energy? This is closely related to the correct explanation of mass defect.
I did some research of that topic and cannot come to a single comprehensive and consistent ...
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2answers
128 views
Mass defect- From where mass is being lost?
As a school student, I have wondered while studying mass defect the following mysterious problem
My assumption
Just like a car's mass is constituted by each part of it(i.e total mass of car will be ...
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1answer
78 views
Mass-energy equivalence and Newton's Second Law of motion
According to Einstein's Mass-energy equivalence,
$ E = mc^2$ OR
$ m = \frac E{c^2}$..... (1)
and According to Newton's Second Law of motion,
$ F = ma$ OR $m = \frac Fa$ ..... (2)
If we compare eq. ...
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4answers
665 views
Does the mass of an object change as it moves away from the earth?
The mass of a helium nucleus is less than the mass of two isolated protons and two isolated neutrons. When the component hadrons are assembled, this mass is lost as energy ($E=mc^2$). This makes it ...
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4answers
346 views
Does $p=mc$ hold for photons?
Known that $E=hf$, $p=hf/c=h/\lambda$, then if $p=mc$, where $m$ is the (relativistic) mass, then $E=mc^2$ follows directly as an algebraic fact. Is this the case?
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Einstein's mass-energy relation
Suppose we have 1 kg of wood and 1 kg of uranium and if we need to find out how much energy would each of the substance give, we'd have to use Einstein's mass-energy relation as follows:
In the case ...
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5answers
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Conversion of mass to energy in chemical/nuclear reactions
Is mass converted into energy in exothermic chemical / nuclear reactions?
My (A Level) knowledge of chemistry suggests that this isn't the case. In a simple burning reaction, e.g. $C+O_2\to ...
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2answers
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Mass-Energy Equivalency
We call $E=mc^2$ the Mass-Energy Equivalency because it equates mass and energy together. But, by that same logic, shouldn't we call $E=\frac{1}{2}(mv^2)$, the equation of kinetic energy in Newtonian ...
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storing energy (as mass)
When chemical energy is released mass is reduced, if only by a negligible amount. Presumably that's true for all energy. And presumably that works in reverse as well: storing energy involves an ...
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0answers
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How many orders of magnitude in energy spans the domain of validity of the Standard Model?
I am wondering if it makes sense to state that the upper limit is roughly 1012 eV (up to know the physics probed by the LHC seems to be pretty consistent with the SM) and the lower one is ... the ...
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0answers
63 views
How fission and fusion create energy? [duplicate]
Possible Duplicate:
How to explain $E=mc^2$ mass defect in fission/fusion
In order for energy to be released, mass has to be "lost", because mass is a form of energy.
In my science class, ...
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5answers
465 views
Why doesn't fusion contradict the 1st law of thermodynamics?
I was reading up on the 1st law of thermodynamics for my Chemistry exam and I was wondering why doesn't fusion contradict the 1st law of thermodynamics?
The 1st law states that
The energy of an ...
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4answers
123 views
Does everything with mass or energy have a gravitational pull?
As small as it may be, does every 'thing' have a gravitational pull? That is, something with mass or energy. No matter how obsolete or negligible it may be, is it there? If so, how is it calculated? ...
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2answers
151 views
Is there any law that prevents an object with mass to become massless?
I got into a discussion with my physics teacher about the speed of light and I asked
What if an object with mass was to lose mass as it gained speed-- would that allow for an object to eventually ...
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2answers
381 views
Why the energy of a marshmallow is so huge?
In this comment in a blog kudzu computes the energy of a marshmallow with mass $M=25 grams$ by using $E=mc^2$:
$E=Mc^2 = 2.247\times 10^{+15} Joules$
I may be wrong but this seems like a huge energy ...
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6answers
2k views
What is Energy made of?
We have the famous equation $E = mc^2$, and we also believe that matter is made of particles.
Then, What is the energy made of? If the two are interchangeable, there must be some common building ...
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1answer
147 views
Man on treadmill and energy/mass conservation
Suppose we put a very obese man inside a large air tight isolated room with a treadmill and he runs on the treadmill for 24 hours and at the end of the day he sees his weight has come down (mostly ...
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2answers
105 views
How is an ideal mirrored box of photons distinguishable from massive particles?
Suppose you have an ideal mirrored box that contains enough photons as to have a relativistic mass equivalent to the [rest mass + kinetic energy] of an electron. In other words, the two systems have ...
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1answer
135 views
Atomic weight in respect to the binding energy?
My book says that the weight of helium (with the nucleon number of 4 and proton of 2) is that of $6,6447*10^{-27}$ kg. Earlier the book stated that if the proton number is left out it means that the ...
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1answer
104 views
Can non-free forces change the rest mass?
While reading Hobsen et al.'s "General Relativity: An Introduction for Physicists", I came across a bit confusing derivation. Multiplying the 4-force and 4-velocity, the following derivation can be ...
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2answers
336 views
Mass in terms of energy
Given the relationships between mass and energy in relativity, and given that particles with mass can be created given energy over the threshold energy, and vice-versa, can we say that mass is simply ...
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2answers
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Calculating the mass equivalency of a song?
I've recently become fascinated with the idea of sound energy having a theoretical equivalent mass. I've read over this thread:
Do light and sound waves have mass
I understand this part: ...
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2answers
504 views
Why does an object with higher speed gain more (relativistic) mass?
Today, in my high school physics class, we had an introductory class on electromagnetism. My teacher explained at some point that an object with a very high speed (he said it started to get somewhat ...
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6answers
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What can $E=mc^2$ do?
In the famous equation $E=mc^2$, the variables stand for:
$E$ is energy, $m$ is mass, and $c$ is the speed of light (in vacuum).
And I understand the equation fairly but limited in knowing in ...
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3answers
206 views
Mechanism for the gravitational field generated by photons
This question follows from a schooling I received in this thread.
I figured that photons do not interact with gravity, except when they've spontaneously converted into a particle-antiparticle pair. ...
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2answers
100 views
Negative potential energy of gravity
Does the negative potential energy in the gravitational field have to be considered in calculating the total mass of the system in question (because of $E=mc^2$)?
If so it seems to me that the ...
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2answers
159 views
Does infinite energy imply Infinite mass (and vice versa)?
If some kind of source was able to supply an infinite amount of energy, does that imply that it also must have an infinite mass? Is the contrary also true?
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244 views
Why do photons add mass to a black hole?
Why do photons add mass to a black hole?
When photons are taken irreversibly into a black hole does the mass of the BH increase?
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2answers
232 views
Einstein's Mass-Energy Equivalence versus Quantum Kinetic Energy
Using a naive view of Einstein's Energy Mass Equivalence $E=mc^2$ (where m is mass and c is the speed of light), it seems tempting to interpret this as a quantum mechanical version of the inherent ...
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2answers
173 views
The time component is $\gamma m c$, so shouldn't $E=mc$?
Basically, the book is Brian Cox's Why Does $E=mc^2$?: (And Why Should We Care?).
I just finished Chapter 5, where we derived the spacetime momentum vector (energy-momentum four vector, as he ...
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3answers
125 views
Universe to energy
Would it violate any known laws of physics to construct a universe containing no mass, only energy?
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2answers
103 views
Does the mass of a falling body decrease?
Let's say a body with m=2kg falls from 100 meters. Obviously it's speed would be far lower than the speed of light so the change in mass (if it exists) would be very tiny. However, I know that if the ...
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2answers
97 views
Is the mass to energy physical process an exact mirror of the energy to mass process?
For my level of understanding the only explanation of mass to energy, ie nuclear weaponry, is limited to a simple summing game where a mass deficit is expressed as energy. For the 'reverse' process, ...
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1answer
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Conversion of energy to mass with radioactive decay
Consider the following problem:
The nuclei of Am-241 decay by the emission of $\alpha$-particles with a kinetic speed of $8.8 \cdot 10^{-19} J$. In a certain source of Am-241 there are $ 4.0 \cdot ...
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3answers
516 views
Getting from $E^2 - p^2c^2 = m^2c^4$ to $E = \gamma mc^2$
What is each mathematical step (in detail) that one would take to get from:
$E^2 - p^2c^2 = m^2c^4$
to
$E = \gamma mc^2$,
where $\gamma$ is the relativistic dilation factor.
This is for an ...
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1answer
99 views
Photons, no energy? [duplicate]
I am only 14, so I don't know much about physics, and I would appreciate help on this topic.
A photon, is said to have 0 mass. However, they carry energy, as electromagnetic radiation. Albert ...
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1answer
77 views
Developments originating from $E=mc^2$
What kind of significant impacts have originated from $E=mc^2$.
Generally, it is regarded as the most famous equation of all time. Except for nuclear energy (fission and fusion) I do not know any ...
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1answer
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Gravitational potential energy with regards to annihilation
Given particles A, B, C and D, where:
A and B have an equivalent mass
C and D have an equivalent mass, both larger than A (or B)
D is the antiparticle of C.
A and B start close to C, but with ...
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1answer
53 views
Non-conversion of mass & energy?
This article is certainly an interesting alternative perspective, but is it factual or does it contain fallacies?
http://www.circlon-theory.com/HTML/EmcFallacies.html
Are mass and energy not ...
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2answers
190 views
Photons in a gravitational field
I have been really staring for a while in a MP-Beiser book and I totally disagree with a statement he does there. On a page 85 he states that photons act as they have a mass $m$. He derives this by ...
