Questions tagged [mass]
The property of an object that determines how much it responds to a force in Newtonian mechanics, and how much it interacts with gravity in the Newtonian framework. Mass also refers to the intrinsic energy of a particle in particle physics. This tag does also cover effective mass.
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Looking for a graph of the running of the electron mass
Is there a graph somewhere showing how the electron mass changes with energy up to around the Planck scale assuming that the pure standard model is always valid (thus no GUT, no Susy)?
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Time dilation rotating around the center of mass
If 2 objects connected by a massless rod or wire, rotate around the center of mass, do they experience time dilation ? I'm thinking that the smaller one will move faster so time will pass slowly, but ...
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Does Rydberg constant vary with mass? [closed]
Does Rydberg constant vary with mass? I researched a bit and some sources say it doesn't depend on mass of the element. How is this possible? Doesn't the name itself say its a constant?
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Why do the Schrödinger and Dirac equations contain the mass?
I know the Schrödinger equation is bascially the "quantized" Hamiltonian formalism from classical mechanics, and the Dirac equation is the special-relativistic version. But these equations ...
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Why does an alpha particle traveling at the same speed as a beta particle have 'only' about twenty times the energy? Rather than over seven thousand? [closed]
An alpha particle travels at about half the speed as a beta particle, right? ~5% of light speed versus ~10%?
Therefore, if you doubled its velocity, its energy would roughly quadruple, correct? (Or ...
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What is the precise running of the electron mass to one loop? [closed]
To one loop, the electron mass $m(E)$ runs with energy $E$ (corrected with the help of Ghoster) as
$$m(E)= m \left [ 1 - \frac{3\alpha}{2\pi} \, \left (\ln\frac{E}{m c^2} + 2/3 \right ) \right ]$$
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Violation of Newton's second law if the mass if changing?
I learned some thing called Galilean principle of relativity which says that two inertial frames are equivalent and the laws of physics are the same in both inertial frames.
However here comes the ...
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Lagrangian for a free antimatter particle
Context
The Lagrangian, $L$, of a free particle is derived many places including in Section 8 of Landau's Theory of Classical Fields. The well-known result for a free material particle of mass $m$ and ...
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What is definition of weight?
What is definition of weight? Does weight of an object change under water, or the weight remains the same, but the: 'apparent weight' = 'weight' - 'buoyant force' ?
Same question for object submerged ...
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How did Newton determine the average density of Earth is twice the density of the surface rocks? [closed]
I've read that Newton determined the average density of Earth is twice the density of the surface rocks, but I can't find his computation anywhere. I presume he used the differential calculus in some ...
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Cobalt atomic mass less than 100 % isotope mass? [closed]
Why is cobalt's atomic mass listed on periodic tables as less than 59 amu when its main isotope (virtually 100 %) is cobalt 59 with a trace of cobalt 60? After reading a bit I'm wondering if it has to ...
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Relativistic mass and relativistic charge
Let a particle with a mass $m$ and a charge $q$ move with a speed $v$ close to the speed of light ($v\approx c$). Then, the special theory of relativity tells us the particle's relativistic mass would ...
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How to calculate time needed by an object to change its state of motion when an net force applies to it (inertia)?
(Newton's first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force. This tendency to "...
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Equation for relative Kinetic energy
Relative Kinetic energy is given by
K.E = ($\gamma$-1)$m_0$c²; where $m_0$ is rest mass
but can it also be given by this
K.E= $\frac{1}{2}\gamma m_0v²$;
where v is velocity of particle
can it?
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Mass in de Broglie Formula
Regarding de Broglie formula
$$\lambda= h/mv$$
here m is relative mass or rest mass?
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Does most of the Universe's mass come from pions (or 'virtual' pions) rather than gluons and quarks?
After the discovery of the Higgs boson, we were all told that most of a proton's or neutron's mass does not actually come from their three main ('valence') quarks and their interaction with the Higgs, ...
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What is the physical explanation for $ cm(h_{min})= h_{min} $ when minimising the centre of mass of a can of coke?
There's an undergraduate statics problem that is about finding the lowest centre of mass of a coke can as it is emptied out (say through a weightless straw). The problem itself is not difficult and ...
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Can it be efficient to move by changing the center of mass?
(Note, I'm not a physics expert.)
Imagine an elongated (oblong) device with some liquid inside. This device can change its center of mass by changing the distribution of the liquid. Let's say, the ...
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Why does beta particles deviate more than alpha particles?
So two figures are given in my book,
One is Deflection of radioactive radiations in magnetic field
and the other is deflection of radiations in an electric field
So the question is why does beta ...
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Mass/weight in 2 places at the same time
Though it may seem like it is not, this is a genuine question of which I cannot find the answer online. The situation of how the question arose may make it seem otherwise.
I monitor my weight every ...
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Lightspeed and Mass=Gravity [duplicate]
As an object approaches the speed of light, its observed mass becomes infinitely large -- Does the Gravity of the object show a corresponding increase and become infinitely large?
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Mass balance for gas in a fixed volume
I am trying to generate an equation that describes the mass balance of a gas in a fixed volume. The application is simulating the sweep out time of the cell in a laser-based instrument which measures ...
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Shouldn't there be a gravitational field without any mass in our 3d space? [closed]
Imagine there is a Neutron star Displaced a small distance from our accessible 3d slice in the direction transverse to that 3d slice. It will bend the space around it. It will also bend the space of ...
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Does anti-gravitating antimatter break any physical principles?
Other than experimental facts that antimatter gravitates the same as matter does, is there theoretically a reason why antiparticles can't create repulsive gravity?
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If falling coconut has more momentum than a bullet then why bullet is more deadly? [closed]
Imagine a coconut of mass 1kg is falling from a 10m tall tree, the momentum is around 14kg.m/s (I don't know how to format my work but just trust me)
and then the momentum of a bullet of mass 0.01kg ...
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Measurement of the velocity of a celestial body by means of (relativistic and classical) gravitational effects on clocks
Imagine a planet with the same properties as Earth, this time moving in an elliptical orbit around a black hole of a large number of solar masses. Also imagine that the surface of this planet is as ...
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If most of an atom's mass comes from binding energy, why did people think that anti-hydrogen could fall up if antimatter had negative mass?
Antimatter isn't bound by anti-energy, so doesn't that mean that even if elementary antimatter particles had negative mass, the total mass of an anti-atom would still be overwhelmingly positive?
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Thermal conductivity from the mass distribution of an object
Thermal conductivity is a property normally related to material. But it is also possible to relate it to objects.
Consider two objects of different shapes made by the same homogeneous material. How ...
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If matter is a form of energy, can it be converted into another form of energy?
I have been told that energy and mass are the same. What puzzles me is why don't we use the same units of measure for both if they are the same? The unit of mass is kg and the unit of energy is the ...
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Buoyancy: True mass (2nd law of newton and density ratio) [closed]
How can I calculate the true mass of an object in a fluid (f.e. air)?
Given:
force measurement (F = 863000 N)
air density (rhoA = 1,29 kg/m^3)
object density (rhoO = 1100 kg/m^3)
g (g = 9,807 m/s^2)
...
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Is electric charge dependent on mass of an object? [closed]
I got this question while reading about electrons and protons where electrons having less mass than protons but possess the same amount of electric charge,though negative.
Could you please elaborate ...
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Energy and momentum & the relation between them
I am trying to wrap my head around energy, mass and momentum, especially in the more general scope of special relativity where massless objects moving at the speed of light also have momentum. So I am ...
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The Komar mass of the second Killing vector in the Schwarzschild metric
In David Tong's lectures on general relativity the interpretation of the $M$ which appears in Schwarschild metric:
$$ds^2=-\left(1-\frac{2GM}{r}\right)dt^2+\left(1-\frac{2GM}{r}\right)^{-1}dr^2+r^2\...
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Why is mass so variable in elementary particles compared to charge, spin, etc [duplicate]
Why is it that the standard model gives very even charge and spin for elementary particles that can easily be compared to each other as integers and simple 1/2, 1/3, fractions whereas some particles ...
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Massless limit of the Dirac theory
What is the physical reason why there is no mixing between left-handed and right-handed Weyl spinors in the massless case of the Dirac theory?
Why does the chirality of a massive particle change ...
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Minimal mass of (Schwarzchild) black hole [duplicate]
After interesting presentation at academic days of emeritus professor of the University of Ljubljana (UL) Andrej Čadež about a notion and detecting of gravitational waves in 2016 an answer arose >...
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If I proposed that two parting photons have mass, how would I quantify that mass?
While an individual photon has no rest frame, when two photons move apart, it makes sense to ask where their centre of mass is, as described here.
If I proposed that while a photon has no mass, a ...
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How is negative mass related to string theory according to Eric Weinstein?
Eric Weinstein suggest in his interview that string theory comes from Hermann Bondi's famous paper related to negative mass in 1957 Chapel Hill Conference and that gravitoelectromagnetism and string ...
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What is momentum exactly? [duplicate]
What is momentum exactly? I am confused that, is momentum a property of particle or something different.
Whenever i look for it's definition it is product of mass and velocity of a particle.
At ...
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Why would it be (or it be not) valid to take that neutrinos can follow the same path as null geodesics?
Basically my main question is the one in the heading of my post, because apparently "Gravitation" by Misner, Thorne and Wheeler takes it directly as true and valid (a common place for null ...
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Unsure of the meaning of $F=ma$ [closed]
If I strike an object with mass $1$ kg with a force of $1$ N (let's say in space), would that object continue to travel in space with an acceleration of $1$ $m/s^2$? My intuition suggests that it ...
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First law of motion of a body with changing mass
The first law of motion states that :
"Every body continues in its state of rest, or of uniform motion in a
straight line, unless it is compelled to change that state by forces
impressed upon ...
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Is there a unified conceptual definition of mass?
Last night I posted this question: Since light has inertia and experiences gravity, what does it mean for photons to be massless?, which I now think was overly wordy and didn't properly express what I ...
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Since light has inertia and experiences gravity, what does it mean for photons to be massless?
I've been trying for a long time to figure out what the heck mass even IS. In introductory physics and chemistry, students are told that massive objects are those that are made of matter and take up ...
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In special relativity, is mass considered as $\gamma m$ or is only the momentum considered as $\gamma mv$?
I am trying to solve the equation of motion of free-falling object considering relativistic effects.
I am not sure the force on the object is whether $\gamma mg$ or just $mg$ where $m$ is the rest ...
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Neutrino propagates and becomes three mass neutrinos?
Neutrinos are produced as flavor eigenstates (coherent linear combination of mass eigenstates). If the distance traveled is large enough, the wave packages of the mass eigenstates will not overlap ...
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How does light not have mass? [duplicate]
How is it possible for light to have zero mass because it was my understanding that in order for "stuff" to exist it has to have some form of mass? And if it does not have mass then can it ...
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What am I doing wrong in my derivation of relativistic mass? [duplicate]
Recently I've been trying to derive some of relativity by myself, where $c=1$.
I believe I derived the correct worldline formula for an object under constant force in 1+1 dimensions, which is a ...
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Do certain quasi-particles really have negative mass?
Do phonons for example really have negative mass or does it just seem like they have negative mass? Could one use the negative mass of certain quasi particles to meet the negative energy requirements ...
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Mass of an object [duplicate]
The mass is said to be matter content of an object. Is there any detailed definition of mass because the phrase , "matter content of an object" uses the word matter whose definition is ...