The special-relativistic relation connecting energy with (rest) mass, $ E^2 - (m c^2)^2= (pc)^2 $. May be used to provide accounting constraints in energy and momentum, both conserved in total, even in reactions where m is not. Use for all manifestations or consequences of the relation.

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4answers
111 views

What is mass constituted by quarks in a proton?

In a question I read Quarks in a hadron- where does the mass come from "The sum of the masses of the quarks in a proton is approximately $30~\text{MeV}/c^2$, whereas the mass of a proton is $931~\...
1
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4answers
121 views

Where does the energy lost due to light emission come from?

If an object lose energy when it emits light, does that energy come from the mass of the object? Examples: Does a flashlight lose mass when it's turned on? Does a regular object (like a pencil or a ...
5
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2answers
207 views

Does the mass lost by merging black holes depend on how they merged?

We've all heard the news about the detection by gravitational waves of two black holes, one 29 solar masses and the other 36 solar masses, spiraling into each other to create a single black hole of 62 ...
4
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1answer
111 views

Does gravitational waves add mass to black hole?

Due to the recent discovery of gravitational waves by LIGO I was wondering suppose a black hole stood between a gravitational wave then due to the fact that black hole can attract every thing then ...
1
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1answer
207 views

Energy Conversion from Mass to Gravitational Wave

How is mass converted to gravitational wave energy by inspiralling binary black holes? Is the gravitational wave energy coming purely from the kinetic energy/gravitational potential of the two black ...
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4answers
72 views

Are there any known non-zero mass objects travelling at almost $c$ observed in the universe so far?

Have we ever observed a body or particle with non zero mass traveling at almost $c$? I'm asking this because according to relativity as an object approaches light speed it's mass approaches infinity, ...
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1answer
31 views

What would the (simplified) formula for the gravity assist look like if mass were introduced as one of the variables?

The (simplified for laymen) formula for calculating the velocity a probe would gain via the flyby of a planet is: The Resulting Velocity of the Probe Relative to the Sun = v + 2U ... where v is ...
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1answer
32 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 ...
1
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2answers
73 views

Conversion of energy to matter? [closed]

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 "mechanism"...
0
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0answers
20 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 ...
0
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0answers
59 views

Photon has energy but no mass [duplicate]

The photons energy is defined as Plancks contant multiplied by the frequency of the light wawe it represents. However Einstein states that the total energy of a particle with rest mass $m$ is $m$ ...
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
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2answers
104 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
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1answer
48 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 ...
0
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0answers
34 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 ...
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2answers
134 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 ...
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3answers
286 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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1answer
32 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 ...
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1answer
90 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 ...
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2answers
141 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 ...
2
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0answers
95 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 ...
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1answer
105 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 ...
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1answer
72 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?
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1answer
146 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. ...
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1answer
42 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 ...
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2answers
140 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. ...
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2answers
109 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 ...
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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 ...
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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
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1answer
159 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 ...
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.
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2answers
210 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
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1answer
51 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
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3answers
335 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 ...
1
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1answer
109 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
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0answers
22 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
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1answer
118 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
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2answers
125 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 ...
1
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1answer
194 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. ...
1
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1answer
106 views

Would it be safe to say that mass is kind of a property of energy?

In a video i just saw about the true meaning of E=mc2, it said something that really got me thinking; "Mass is not really converted to energy" and that mass wasn't actually a thing, but more of a ...
4
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2answers
60 views

How do radio signals contribute to gravity?

First, the inspiration for this question: I just read that it takes one hour to send a picture from the New Horizons space probe, to Earth. It also takes around 5 hours for that picture to reach ...
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1answer
119 views

Will I weigh more if I have fever?

$E=mc^2$ means that energy is mass, and adding energy to an object (that is, making it hotter) makes it more massive. So if my body temperature increases, will I weigh more? or will i become lighter ...
0
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2answers
71 views

Does chemical energy contribute to mass? [duplicate]

Does chemical energy contribute to the mass of an object? I don't mean the bond energy, but the possible energy that could be released (i.e. Does an atom of oxygen and a molecule of hydrogen (H2) have ...
1
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1answer
640 views

Is $E=\hbar \omega$ correct for massive particles?

From Planck's relation we can say that the energy of a photon is $$E=h\nu=\hbar \omega \, .$$ where $\hbar \equiv h / 2\pi$. On the other hand, the energy of a free particle can be expressed as $$E=...
0
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2answers
173 views

In a nuclear reaction, where does the energy go?

Lets say two hydrogen fuse together, where does the energy released go? Is it carried away as momentum imparted on the helium atom? Is it carried away in neutrinos? Is it carried away as gamma rays? ...
4
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3answers
182 views

What experiments have been done that confirm $E=mc^2$?

What experiments have been done that confirm $E=mc^2$? Are there experimental results that contradict $E=mc^2$? Or are experimental results consistently showing this famous formula to be true?
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3answers
217 views

What happens to a particle and antiparticle that collide?

Matter can never be destroyed, so what happens to those particles? Do they just disappear? Where does the mass go?
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1answer
180 views

Mass loss for Fusion energy? [closed]

I am thinking how you can estimate the mass loss of the fusion energy for 1 kWh. I think you cannot use Einstein's $E=mc^2$ to calculate the mass loss in the fusion reaction of the Sun. How can ...
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1answer
120 views

Mass of a particle ( relativity)

A hypothetical atom has a rest mass of $15.000000136\,\mathrm{u}$. Overtime it undergoes a spontaneous breakdown into two masses of $7.000000229\,\mathrm{u}$ and $6.902727019\,\mathrm{u}$ respectively....
2
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1answer
70 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 ...