New answers tagged mass
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Assuming the photon has a moving mass, why current quantum mechanics is unable to prove or deny it?
This question has been beat to death here, a quick search should give you more details. So, in a nutshell:
Non-relativistic quantum mechanics doesn't describe massless particles well.
In a ...
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Force of an accelerating ball?
But if I were to drop the same ball from a greater height, why would it hit the ground harder, with greater force?
Yes, it's right. Because when the ball falls from a greater height it has more ...
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Force of an accelerating ball?
At the exact moment of impact, is the ball still in free-fall? Is there not a change in momentum due to something other than gravity during the impact?
The velocity changes over some (probably very ...
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Force of an accelerating ball?
Newtons second law actually states that force on a body is the "rate of change of momentum". So if a ball is dropped from a greater height, it has more velocity as compared to it being ...
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Accepted
Do electrons have inertia?
Inertia is the resistance of any physical object to a change in its velocity. This includes changes to the object's speed, or direction of motion. An aspect of this property is the tendency of objects ...
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Do electrons have inertia?
Despite quantum effects an electron without external forces will act as any other macroscopic object without external forces. In particular it will not accelerate by itself and it has constant inertia....
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Do electrons have inertia?
In physics, the phenomenon of inertia is in a category where an exhaustive explanation for it is not available (and may never be). The point is: in order to have a theory of physics at all the ...
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What would be the value of $c$ where $c$ is the speed of light?
The full equation is $$E^2 = (m_{0}c^2)^2 + (pc)^2$$
For light, $m_{0} = 0$, then $E = pc$
The momentum of light is non zero, which can either be derived from photons, or electromagnetic theory.
If $...
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What would be the value of $c$ where $c$ is the speed of light?
Different meanings of the word "mass". Revisionists have redefined "mass" to mean "rest mass", thus sowing massive confusion. The photon has no rest mass. In revisionist ...
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How does massless particles arise in string theory when it starts with the assumption that all strings are composed of massive little pieces?
Susskind corrects himself at 1:00:08 where he says that the "mass density" coefficient in front of the $\dot{X}^2$ term is a non-relativistic analogue; it is not actually a mass-density of ...
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How does massless particles arise in string theory when it starts with the assumption that all strings are composed of massive little pieces?
Here is a somewhat hand waving explanation that I think is appropriate given the nature of the question. The equations for the positions of the little masses along the string is essentially a wave ...
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Extension in Massive Springs under gravity
The trick is to evaluate the load situation of a slice of lenght $\Delta h$. As it is at rest, the downward force at the bottom of the slice $(F_h)$, plus the weight of the slice must be equal to the ...
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What is the general dependence of volume change from mass change due to general relativity?
That means ΔV increases linearly with M. Now, I'm wondering whether this is valid in general or only regarding the earth? Is that ("ΔV increases linearily with M") an inference out of ...
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Effect of object mass in coeficient of restitution
The coefficient of restitution of the ball can be expressed as the ratio of momenta before and after impact. Since the mass of the ball does not change, it cancels out leaving only the ratio of ...
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Effect of object mass in coeficient of restitution
The masses affect the magnitude of impulse in a collision.
Consider two bodies of mass $m_1$ and $m_2$ about to collide with relative velocity $v_{\rm rel} = v_2 - v_1$.
Considering the coefficient of ...
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Why does Newton's second law involve mass?
Mass requires input of energy to accelerate...Newton's second law is a description of the changes that a force can produce on the motion of a body, not what the body adheres to on the substantive ...
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Why does Newton's second law involve mass?
Newton's second law states that the force experienced by a body is vectorially equal to the rate of change of its momentum which is defined as mv. For a fixed mass, this rate reduces to the familiar ...
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Nuclear fusion mass defect and energy production
. . . . . which in turn increases the binding energy between the nucleons. What is the origin of this extra energy? What is the cause of this energy?.
I think you have misunderstood the idea of ...
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Nuclear fusion mass defect and energy production
This answer and the accompanying discussion may be helpful to you
https://physics.stackexchange.com/a/667132/313823
It is really no different from a chemical reaction like
$$H+OH \longrightarrow H_2O ...
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Kinetic energy of quarks and mass of proton
I assume the energy carried by the gluons is referring to the binding energy of the three quarks by the strong force.
It is more complicated than this. See how the strong interaction is figuratively ...
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A ball of mass 22g moves to the left at a speed of 35 m / s
Use the work-energy theorem. The work-energy theorem says that the work done on a body by external forces on it is equal to the change in the kinetic energy of the body. Recall that kinetic energy ...
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Fusion energy origin
The helium nucleus (for instance) has 2 protons and no neutrons-the mass remains the same, so why did the mass defect occur?
Helium nucleus contains two protons and one or two neutrons (depending on ...
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Abraham-Lorentz force/electromagnetic mass/relativistic mass
Aka, charged objects seem to have more inertial mass, than neutral objects.
This idea is confirmed by experiments done by Thomson
What does "charged objects have more mass than neutral ones&...
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Abraham-Lorentz force/electromagnetic mass/relativistic mass
If a body is un charged, how do we know that the same rules apply? As for a neutral object, we cannot test whether or not maxwells equations apply.
We can, and all experiments are consistent with ...
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Abraham-Lorentz force/electromagnetic mass/relativistic mass
First, the concept of relativistic mass has been discarded by the scientific community for decades now. Einstein wrote against using the concept back in 1948. Okun was particularly strong against the ...
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Is gravity a direct result of Lorentz Contraction?
No. Special relativity on its own doesn't imply general relativity. It's not enough to have some invariance principles; you need to "turn on" mass-energy gravitating by specifying how they ...
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Would you run faster on Mars?
Summary
All else being equal, runners on Earth will accelerate harder up front, but runners on Mars will have higher top speeds. As such, longer runs will favor Mars, while shorter runs will favor ...
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Would you run faster on Mars?
This is a partial answer.
Anyone who has run on an Alter-G treadmill will tell you that it is much easier to run at a given speed when your weight is artificially reduced in the way that Alter-G's do. ...
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What is the mass of collective oscillations?
My naïve guess would be that it has something to do with a derivative of the dispersion relationship similar to the effective mass of Bloch electrons, but I haven't seen a definitive answer.
This is ...
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Would you run faster on Mars?
(a fork of Carl’s answer)
Your question is interesting but perhaps a bit ill-posed. Consider, for example, the difference between a 100-m sprinter and a marathoner or jogger. The sprinter will lean as ...
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Would you run faster on Mars?
You question is interesting but perhaps a bit ill-posed. Consider, for example, the difference between a 100-m sprinter and a miler. The sprinter will lean as far forwards as possible so as to ...
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Accepted
Would you run faster on Mars?
The speed of walking and running depend on pendulum-like motion of the legs. If you walk at different speeds the power used varies, and has a minimum roughly corresponding to the free pendulum motion ...
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Would you run faster on Mars?
Buoyancy is not what slows the motion of astronauts on the Moon. Buoyancy requires some heavier-than-you liquid to surround you (in order to impede you significantly). When vacuum surrounds you there'...
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Why relativistic mass of a body increases with its speed?
The abrupt answer to your question is: because you defined it that way.
The arrogant answer: no physicist uses relativistic mass.
The useful answer: relativistic mass is really not a useful quantity, ...
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Why relativistic mass of a body increases with its speed?
I mean, "why" is a fun question because you're eventually destined to just get an "because the universe says so" answer, but I'll try and give the
shortest, most intuitive ...
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Conservation of mass from material derivative
Both forms are perfectly consistent in the particular case that the divergence of the 3-D vector field is zero. Recall, that the mass continuity equation can also be written as:
$$\frac{D\rho}{Dt}=-\...
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Why relativistic mass of a body increases with its speed?
I suggest you think of it in the following way...
Newton's laws tell us that when you apply a force to an object, the resulting acceleration is inversely proportional to the mass of the object. So you ...
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Why relativistic mass of a body increases with its speed?
Special relativity was originally proposed by Albert Einstein in a paper published on 26 September 1905 titled "On the Electrodynamics of Moving Bodies". The incompatibility of Newtonian ...
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Why relativistic mass of a body increases with its speed?
Let's rewrite this using $E=mc^2$ to show how the energy increases with velocity
\begin{equation}
E = m c^2 = \frac{m_0 c^2}{\sqrt{1-\frac{v^2}{c^2}}}
\end{equation}
Hopefully it is intuitive that the ...
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