Questions tagged [mass-energy]
The special-relativistic relation connecting energy with 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.
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Can a big mass defect make the mass negative?
Can two particles with small masses and a strong attractive interaction have a total negative mass when brought together?
Let $m_1, m_2$ be the (rest) masses of two particles when infinitely distant. ...
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Is a photon truly massless? [duplicate]
First of all, I am not a physicist or mathematician, not even a hobbyist but the following statements have always puzzled me:
$E=mc^2$
A photon is a desecrated particle of energy.
A photon is ...
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If a proton transforms into a neutron by releasing a positron why should this process create more mass? [duplicate]
If waves can interfere and thats why cancel out or add up why we cannot think the same about the natterial feature called mass as in this explained example in the title of this posted question??Thanks ...
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Why is the mass-energy graph for atomic mass $A=98$ not quadratic?
For fixed atomic mass $A$ and varying atomic number $Z,$ the mass of the nucleus is quadratic in $Z$. Were it possible for $Z$ to vary continuously, we'd have at most one local minimum. Since we are ...
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Why the Sun has a higher temperature than humans?
Why the Sun has a higher temperature than humans if the energy/gramme of matter ratio of humans is greater than that of the Sun?
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"Mass Shell" Condition on Euclidean Scalar Field
This is a basic qft question. I am looking for the condition on a free scalar $\phi$ of mass $m$ in Euclidean space such that it satisfies the Klein-Gordon equation.
The Euclidean space Klein-Gordon ...
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Does life erode Earth's mass over time?
Since life converts matter to energy, and there's no natural process that does the opposite (aside from supernovas), does this mean that the mass of our planet is gradually diminishing? I asked ...
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Why does the mass-energy equivalence apply to binding energy when it is derived purely through kinematic means?
I understand that by defining the four velocity, multiplying it by the rest mass and taking the entire thing's norm we get $E^2=m^2+p^2$, but how does this apply to binding energy, or in general ...
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Is the Planck mass the "lower limit" for gravity?
The Planck units are often treated as being the "lower limits" to things: the Planck length for length, the Planck time for time, etc.
But the Planck mass, which is about $2.2\times10^{-5}$ ...
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How does mass-energy equivalence work with chemical bonds? [duplicate]
If you have, for instance, 2 oxygen atoms and do E=mc2 to get their equivalent energy, you get about 2.38nJ. However, if you have diatomic oxygen, there's also the energy of the bond; about 0.8aJ. ...
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What is the total mass-energy of baryonic matter?
From what I understand, conservation of energy does not apply to the total energy of the Universe, because it constantly expands and the new, created space has a constant non-zero energy of its own. ...
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Rest Mass Energy
What exactly is the Rest mass energy? I know the usual goes Like it is total energy stored in mass $m$ that is in Rest. so for someone moving relative to the frame that the mass $m$ is in (a rest ...
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Does dark matter have mass?
When trying to understand what dark matter is, it is helpful to know that some properties of it can already be derived from various observations, such as, it only interacting via gravity and no other ...
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Suppose a shell of a sphere formed by matter and with large radius, start afterwards to diminish the radius, give $E=mc^2$ the system stops
Thinking in classical mechanics terms but with the knowledge that $E=mc^2$ let's make the below thought:
Suppose you have a shell of a sphere formed by a mass uniformly distributed over the surface of ...
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Is the relativistic energy-momentum relation fundamental? [duplicate]
The following relativistic energy-momentum relationship is taken to be fundamental:
$$E^2=p^2c^2+m_0^2c^4.\tag{1}$$
Let us specialize to massless particles ($m_0=0$) so that we have:
$$E=p\ c.\tag{2}$$...
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