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1
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2answers
52 views

Conversion of energy to matter? [on hold]

Now, this answer has sort of been asked before. But I haven't really found the answer that I'm looking for. Exactly what is the mechanism by which energy can be converted into matter? By ...
-1
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1answer
265 views

How does Einstein got equivalent mass - energy equation E=mc2? [duplicate]

How does Einstein got equivalent mass- energy equation E=mc2 ?
1
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1answer
25 views

How can I apply a certain “pressure” (g/cm²) to the ground by dropping a weight?

I'm trying to find a way to apply 100g/cm² to the ground (substrate = snow) by dropping a weight from a particular height. If I drop 250g weight (80cm² area) from 1m, I'll get a velocity of 4.43m/s² ...
0
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1answer
102 views

Conversion of energy to matter or antimatter?

We all know that matter converts into energy, but will energy convert into matter? Does it form antimatter by converting? Illustrate me with example.
4
votes
3answers
255 views

How is it possible for the wavelength of light to change in a medium?

So my physics class has just finished a long unit on optics while at the same time I've been trying to teach myself relativity. I admit my understanding is probably rudimentary, but I figured all the ...
0
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0answers
16 views

What proportion of the mass of the objects that are at rest on earth comes from the motion of earth in space?

According to energy mass equivalence, an addition in kinetic energy always translate into an addition in mass. My question is: What proportion of the mass of the objects that are at rest on earth ...
1
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0answers
19 views

Complete combustion in gas [duplicate]

Does matter simply releases energy in wood burning fire or does some matter actually convert into energy? Blue flame considered as complete combustion but in ceramic plates gas heaters for room ...
2
votes
2answers
70 views

What happens during mass-energy conversion

A mass is another form of energy. When a mass ceases to exist as 'matter', it exists as energy - in the forms of energy we generally know ( light,heat ). But is this so simple? When a mass exists in ...
0
votes
1answer
22 views

determine the mass of ice that melts during the impact

During a storm, a mass $m = 2 g$ hailstone falls to the ground. Its speed just before coming to ground is $v = 18 m / s$. its speed just after is zero. Assume that the hailstone is pure ice, the ...
8
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4answers
3k 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, ...
0
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0answers
32 views

Why is spacetime curved by mass but not charge [duplicate]

According to general relativity theory, the deformation of spacetime is proportional to energy tensor $$T_{\mu\nu}.$$ $$ R_{\mu\nu}-\frac{1}{2}g_{\mu\nu}R = 8\pi G T_{\mu\nu}. $$ Does it mean that ...
24
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3answers
5k views

Why can't I do this to get infinite energy?

I know that I cannot do this because of conservation of energy, so I am looking for an answer as to why this will not work. So by my understanding of Einstein's whole famous $E=mc^2$ thing it is ...
1
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3answers
173 views

Binding Energy of an atom

I would like to know if there is any difference between the binding energy of a nucleus and the binding energy of an atom and what exactly do we mean when we say Binding energy per nucleon.. Edit to ...
0
votes
2answers
121 views

At relativistic speeds, how is an object's increased mass created and distributed?

This question says that, at relativistic speeds, an object's increased mass will result in increased weight or gravitational force. But if we have increased mass and corresponding gravitational ...
1
vote
2answers
246 views

Is there any correlation between mass-energy equivalence and Maxwell's 4th equation?

I wonder, how came in both equations proportionality constant is exactly $c^2$? $$c^2(\nabla \times B) = \partial E/\partial t$$ where $E$ - electric field $$c^2m = E$$ where $E$ - energy I am ...
1
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2answers
133 views

Doubts regarding Einstein's 1905 derivation of mass-energy equivalence

This is a follow up on this question. In his [paper][2] under the title:Does the inertia of a body depend upon its energy-content, Einstein drives the famous $E=mc^2$ equation. His argument can be ...
-1
votes
3answers
188 views

If mass is not conserved but instead energy is conserved, is it right to say that the fundamental particles are photons? [closed]

If mass is not conserved but instead energy is conserved, so is it right to say that the fundamental particle of the Universe is photon instead of protons, neutrons, electrons, leptons, etc and all ...
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2answers
135 views

is following alternative interpretation of total energy possible? E=m'v^2 instead of E=m'c^2 [closed]

I have read the paper, http://arxiv.org/pdf/physics/0206061.pdf "Fundamental Disagreement of Wave Mechanics with Relativity", some time ago, in which the author claims that there is another way to ...
0
votes
1answer
145 views

Where does mass go when energy is converted in to photons?

If matter and anti-matter annihilate each other they emit a photon with the energy that corresponds to the mass, right? This is the best example I could think of matter/energy being converted directly ...
1
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1answer
28 views

Does having inertial mass demand that the particle must have (Higgs and other) potential energy?

My understanding is that a photon is pure kinetic energy and has no inertial mass of its own (or probably too low to be significant). But for a box with two photons whose momentums cancel, the photons ...
4
votes
3answers
4k views

In nuclear fusion reaction, what is the percentage of mass converted to energy?

I read somewhere that it is about one percent of the mass, but I find this too high. Also I have done some calculations, for example, the Tsar Bomba was 50 MT bomb and weighed about 27 tons. Although ...
0
votes
1answer
79 views

Electron decay in high-energy accelerators

As far as I understand, electrons are infinitely stable since they are the least massive particle with non-zero electric charge. However, when accelerated to high-energies, the energy (or mass) of the ...
2
votes
1answer
66 views

Mass - Unification of kinetic and gravitational mass definitions

As a kinetic definition, mass of a body is a measure of the translational inertia of the body. There is also the gravitational definition of mass. Can these definitions (kinetic and gravitational) be ...
8
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4answers
423 views

A question about $E=pc$ for massless particles

Since photon has no (rest)mass and $$E^2=(pc)^2+(mc^2)^2$$ we derive that $E=pc$ for particle with no (rest)mass. However, if we transform the non-relativistic formula for kinetic energy ...
2
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0answers
65 views

Gravitational mass defect

In nuclear physics we have a mass defect by the binding energy of the nuclides. A similar effect appears in the theory of gravitation induced by the gravitational binding energy, which reduces the ...
-1
votes
1answer
94 views

If photons have mass then how can they travel at speed of light? [closed]

Anything that has mass must be slower than speed of light. If they are travelling at speed of light they must contain infinite energy which should be able to destroy everything, clearly thats not ...
5
votes
3answers
250 views

Speed of light, lasers and mass

Hopefully this isn't a bad question. Light travels at the speed it does and nothing else can travel that fast because things have mass, correct? Or at least correct on an elementary level. And if ...
41
votes
6answers
8k views

Why do lasers cut? Is this a case of light acting as matter?

All I found in Google was very broad. From a physics models perspective, why can photons emitted from a laser cut? Does this cut mean that the photons are acting like matter?
0
votes
1answer
38 views

How can one interaction influence the way another interaction generates mass?

This question arose as a follow-up of this one and applies generally to all interactions and all ways to generate mass. To make it clear, I take here the example of the neutron, whose mass is in ...
0
votes
1answer
67 views

How can we say that difference in energy between 99.99% and 100% of speed of light is infinite? [duplicate]

How is it not possible for a particle to attain 100% speed of light and what will happen if it attains the speed of light?
63
votes
1answer
2k views

Does the 4/3 problem of classical electromagnetism remain in quantum mechanics?

In Volume II Chapter 28 of the Feymann Lectures on Physics, Feynman discusses the infamous 4/3 problem of classical electromagnetism. Suppose you have a charged particle of radius $a$ and charge $q$ ...
-2
votes
1answer
91 views

Parkhomov's E-cat reproduction [closed]

In the beginning of the year, Professor Alexander Parkhomov of Lomonosov Moscow State University claimed to have replicated (as read in e.g. Wired) of the E-cat functioning, albeit with lower effect. ...
10
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6answers
1k views

Energy and its physical significance

What does it exactly mean when we say that energy has moved from one body to another, what has physically been transferred? The concept of energy is very confusing, please help. And if gravitational ...
1
vote
2answers
203 views

Why do we never account for the extra mass carried by a gravitationally excited object?

The mass of a bound system is the mass of its part minus the binding energy. For instance if you put an electron and a proton together to form a hydrogen atom you get a $13.6 \text{ eV}$ photon and ...
0
votes
2answers
54 views

Energy forms of a charged particle in an electric field?

I am thinking an explicit list of all energy forms in a system of charged particle (take electron or proton, for instance). It has at least potential energy and kinetic energy by Newton. ...
0
votes
2answers
105 views

Einstein's famous equation $E = mc^2$

A fellow engineering student told me many years ago, that $E = mc^2$ means is that as an object of mass $m$ approaches $c$, the speed of light, it's mass increases and, at the speed of light, becomes ...
1
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0answers
26 views

What the common examples of $E=mc^2$? [duplicate]

this theory say's mass convert into energy and energy convert in to mass Whats he example of energy convert into mass?
2
votes
1answer
104 views

An apparent contradiction to $m = m_0/\sqrt{1-v^2/c^2}$ [duplicate]

Using theoretical framework of the special relativity, we can show that the quantity that we classically regard as energy does have a property of inertia. And particularly, if the total energy of a ...
3
votes
4answers
2k views

What is pure energy?

Inside the core of a star thermonuclear fusion reaction fuses hydrogen atom into helium releasing massive heat/light and energy.When a black hole eats up enough stars and gases it devours itself by ...
0
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0answers
30 views

What is the pure form of energy? [duplicate]

What is the pure form of energy? Einstein in his energy mass equation derivation said that electromagnetic radiation is pure form of energy.
0
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1answer
48 views

How can mass be changed into energy? [closed]

I asked this question because of Einstein's equation, he derived an equation saying that solid things are packed ENERGY. So lets think that solid is energy,then why we are not using it for our ...
5
votes
3answers
324 views

Are chemical bonds matter?

So it recently blew my mind that chemical bonds have mass. And that a spring that's wound up similarly weights a little more. But there is a distinction between mass and matter. I believe that a ...
3
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6answers
4k 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 ...
1
vote
1answer
99 views

Can energy be weighed?

The binding energy of nucleus is calculated as- Mass defect = (Total mass of nucleons-Mass of the nucleus) And after that $E=mc^2$ is used for calculating the binding energy. Hot water is heavier ...
0
votes
0answers
21 views

How are mass and density treated in general relativity? [duplicate]

Background: I am confused by how mass relates to the equations in general relativity. For example, given a certain mass density distribution, I am unsure how to express a system in terms of GR. ...
1
vote
1answer
86 views

Why is this nuclear reaction $p\to n+e^++\nu$ forbidden for a free proton? [closed]

Why is this nuclear reaction forbiden for a free proton? $$p\to n+e^++\nu$$ Where $p$ is the proton, $n$ is a neutron, $e^+$ is a positron, and $\nu$ is a neutrino. What i´ve been thinking is because ...
1
vote
2answers
108 views

Does electricity have mass?

Given a superconducting magnetic coil, such as the ones at the LHC, is there a difference in the coil's mass when it is powered down versus when is powered up? Edit: This has been labelled a possible ...
10
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6answers
1k views

Potential energy in $E_f^2=(mc^2)^2+(pc)^2$?

Let's consider $$E_f^2=(mc^2)^2+(pc)^2$$ where the $mc^2$ is the rest energy due to the rest mass -- in Finnish "lepomassa". $$ \sqrt{(mc^2)^2+(pc)^2} - mc^2~=~(\gamma-1)mc^2$$ is the kinetic ...
0
votes
1answer
91 views

Does the rest mass energy include the potential energy of the particle?

The potential energy (as far as I have studied - that is, mainly classical physics) depends on the reference level, since its absolute value cannot be calculated. It can therefore be negative as well. ...
7
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3answers
1k views

Potential energy in Special Relativity

In Special Relativity, the energy of a free particle is $E^2=p^2c^2+m^2c^4$. But what would be the energy when there is potential energy? If it's something like $E=\sqrt{p^2c^2+m^2c^4}+U$, what ...