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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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 ...
0
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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
140 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
92 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
104 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
140 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. ...
0
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1answer
41 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
115 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
107 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?
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1answer
156 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 ...
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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
209 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
50 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 ...
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3answers
332 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 ...
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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 ...
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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. ...
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1answer
110 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 ...
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2answers
122 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 ...
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1answer
163 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
95 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 ...
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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
113 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 ...
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2answers
69 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 ...
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1answer
553 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 ...
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2answers
164 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? ...
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3answers
181 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
210 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
165 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 $6.902727019\,\mathrm{u}$ ...
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 ...
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2answers
829 views

Quarks in a hadron- where does the mass come from

We know that the sum of the masses of the quarks in a proton is approximately $9.4^{+1.9}_{-1.3}~\text{MeV}/c^2$, whereas the mass of a proton is $\approx931~\text{MeV}/c^2$. This extra mass is ...
1
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1answer
107 views

Do photons have no mass? [duplicate]

My Quantum Mechanics' teacher said today on the class that photons don't have mass. I was puzzled because I knew that photons have momentum. If a particle hasn't mass then its momentum sould be $0$ ...
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1answer
66 views

How does fusion work in the Sun if neutrons have more mass than protons?

According to my textbook, the next result of the fusion reactions in the Sun is: 4H -> He + neutrinos + gamma photons However, if hydrogen atoms are basically a proton and helium atoms are 2 protons ...
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2answers
152 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 ...
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2answers
231 views

What is meant by mass defect of a single neutron or a single proton?

As per my understanding The mass defect of a nucleus represents the mass of the energy binding the nucleus, and is the difference between the mass of a nucleus and the sum of the masses of the ...
1
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1answer
76 views

What makes neutron heavier than a proton? [duplicate]

The mass of proton is 1.672*10¯²7 kg while it is 1.675*10¯²7 kg. Both are made up of 3 quarks each. Then what makes proton lighter than a neutron?
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1answer
96 views

What really happens when matter and antimatter combine? [duplicate]

When Energy is converted to matter, we know equal amounts of matter and antimatter are produced. What happens when matter and antimatter combine?
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2answers
117 views

Can matter be formed from nothing? [closed]

Well, I wanted to know whether matter can be created from nothing? Could matter be created in pure vacuum or does it require some energy? If energy is required, How is energy converted to matter? If ...
2
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1answer
167 views

How can we define energy? [duplicate]

Can we call matter without mass as energy? just a simple defintion to the word energy; massless matter= energy? and I'm not asking about photons.
1
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1answer
81 views

Mass and Schwarzschild Radius [duplicate]

Do free massless particles have a Schwarzschild radius? I'm curious about the mass in the equation for the Schwarzschild radius. I know that you can calculate a Schwarzschild radius for any massive ...
2
votes
4answers
136 views

Does a ticking watch have more mass? [duplicate]

In the video on YouTube, The Real Meaning of E=mc² | PBS| Space Time Studios, it claims that a ticking watch has more mass then a non ticking watch due to the intrinsic KE, PE and thermal energy of ...
3
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2answers
117 views

Where does the equation $p=\frac{1}{c}\sqrt{T^2 +2mTc^2}$ come from?

Where does the relativistic formula $$p~=~\frac{1}{c}\sqrt{T^2 +2mTc^2}$$ come from? What is the derivation from Einstein's formula? $T$ is the kinetic energy $m$ is the mass $p$ is the momentum.
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2answers
2k views

Do chemical bonds have mass?

When an exothermic reaction occurs, the energy in the chemical bonds of the reactants is partially transferred to the chemical bonds of the products. The remaining energy is released as heat. For ...
1
vote
1answer
84 views

How are photons effected by gravity? [duplicate]

If we use E²=m²c⁴+p²c², and we know mass of photon is zero, and they have momentum but why aren't they affected by gravity.
0
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2answers
104 views

How does a Black hole attract light? [duplicate]

Please no hate for lack of knowledge: I am somewhat fascinated with the subject of black holes. However, I do not understand a concept which is constantly attributed with black holes: that a black ...
4
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1answer
129 views

Binding energy and mass

I’ve been told that a greater binding energy means the nucleus is more tightly bound, and therefore that decreases the mass of the nucleus with respect to its nucleons when separated. But why does a ...
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2answers
57 views

Can a 0.1mm iron cannonball fired with a proportional cannon damage a tumbler (glass)? [closed]

A teammate just used the well known phrase "a storm in a teacup". I looked at my tumbler (full of water) and asked this question: "If a pirate ship the size of a nutshell had cannons with iron ...