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.

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Can mass be directly measured without measuring its weight?

From Wikipedia, http://en.wikipedia.org/wiki/Mass Inertial mass measures an object's resistance to being accelerated by a force (represented by the relationship F=ma). Active gravitational ...
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7answers
3k views

Why do we have an elementary charge but no elementary mass?

Why do we have an elementary charge $e$ in physics but no elementary mass? Is an elementary mass ruled out by experiment or is an elementary mass forbidden by some theoretical reason?
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0answers
32 views

How can a photon exist on its own without a mass? [duplicate]

For example, thermal energy exists and has no mass, but is carried by particles which have mass. A photon is described as a particle - how can a photon exist on its own, travel in space and even push ...
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1answer
88 views

It seems wrong to find the mass using weight alone when using chemical compounds [duplicate]

The difference between mass and weight is pretty straightforward so then how can we WEIGH a substance then ask how many Daltons (atomic MASS units) are in that substance without a conversion in there ...
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1answer
363 views

Natural frequency of spring-mass system

We can found on internet videos or articles about resonance. For this they for e.g. take a system of two spring and mass in between. When they set force frequency to close to natural frequency. But ...
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2answers
97 views

Is mass in particle physics classical or relativistic?

Is the concept of mass in particle physics relativistic (i.e. mass as described by general relativity) or classical (i.e. mass as described by classical Newtonian physics)?
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2answers
423 views

How can you accurately determine your own mass?

I'm trying to figure out whether it is possible for an individual to accurately determine his/her own mass, to within 100g, using equipment that is readily accessible or can be purchased at a ...
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0answers
306 views

How much energy does a powerlifter need to perform a session of squats?

So I started the math myself and I'm hoping someone can look this over and improve on my idea. Let's say that a powerlifter performs the following sets of squats: % 1RM = lifted weight in percent ...
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1answer
61 views

How to model mechanical systems that change configuration over time?

If I have some simple mechanical system, say - a mass attached to one end of a spring fixed at the other end, I can write differential equations describing such systems which can also be handled ...
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1answer
112 views

What is the definition of inertial mass?

What is the definition of inertial mass? I can see two options, either it's the coefficient associated with the object being accelerated in Newton's 2nd Law, or it's the coefficient relating momentum ...
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3answers
20k views

Why does an object with higher speed gain more (relativistic) mass? [duplicate]

Today, in my high school physics class, we had an introductory class on electromagnetism. My teacher explained at some point that an object with a very high speed (he said it started to get somewhat ...
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2answers
955 views

Special relativity and massless particles

I encountered an assertion that a massless particle moves with fundamental speed c, and this is the consequence of special relativity. Some authors (such as L. Okun) like to prove this assertion with ...
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0answers
55 views

What happens when electromagnetically shunken coin is heated

The question is simple: What happens to coin/object that was electromagnetically shrunken by a coin crusher device is then heated until it (I asume) melts? Do I have misconception or not just ...
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0answers
65 views

Bending of a pipe filled with sand

There is this industrial pipe made out of steel that is 1 meter in diameter and 6 meters long (and volume 4,71 cubic meters). The thickness of the pipe "wall" is 4 centimeter. The pipe is filled ...
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2answers
194 views

Does distance traveled by a vehicle after its engine has been switched off depend on its mass at all?

A vehicle moving with some velocity on a rough horizontal road finally comes to rest after its engine has been turned off. Intuitively, it seems a vehicle with greater mass would stop first because it ...
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1answer
206 views

How do the energy eigenvalues of rotational degrees of freedom in statistical mechanics come about?

I want to understand the hierarchy different degrees of freedom of a mechanical system. Specifically, I want to understand which subsystems equibrilate faster and why. This question comes up: Why ...
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1answer
34 views

Can we measure a mass increase for a system with more energy?

This question is about whether the mass of a particle increases with its speed. Here is my related question from which this question spawned: Why is there a controversy on whether mass increases with ...
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2answers
4k views

Projectile motion without air resistance [closed]

Does the mass of projectile affect its trajectory when it is projected in no air resistance environment and why?
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2answers
499 views

If a photon has no mass, how can it be attracted by the Sun?

I read that the photon doesn't have mass, but my teacher says that the photon has mass because the sun can attract it (like in the experiments to prove the theory of relativity). I think that there ...
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2answers
151 views

Subatomic particle mass and Benford's Law

Nine out of 15 subatomic particle masses begin with the digit one. Benford's Law would imply 30% with one as the leading digit. Is there any significance to this frequency distribution, such as ...
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2answers
147 views

Is negative mass for a bound system of two particles forbidden?

Is there any theorem that forbids the bound system of two massive particles to have negative mass?
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1answer
1k views

Why mass terms are forbidden?

I would like to clarify my understanding on why mass terms in Lagrangians of gauge theories are forbidden. It's often repeated that particle masses are forbidden by electroweak symmetry because it is ...
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1answer
87 views

Measuring mass by acceleration due to electromagnetic forces in free fall

My question is a simple one (I think): How precise will the results be if you attempt to measure the mass of a macroscopic object by measuring it's acceleration when a constant electromagnetic force ...
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1answer
58 views

Mass of small fluctuation around vacuum

For a potential $V$, how do we define the mass of a small fluctuation around its vacuum? For example I have the potential $$ V_\mathrm{eff}(\phi) = \frac{1}{2} \left(\frac{\rho}{M^2} - \mu^2\right) \...
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2answers
280 views

Calories Burned While Hiking [closed]

I want to find out how many calories are burned on any particular hike by any particular by using a formula. I figure it's probably a simple physics question, but since I never took physics, I don't ...
2
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1answer
114 views

How to weigh your nephew [closed]

My nephew is 3 and weighs around 30 pounds I am guessing. However, I would like to weigh him at home. I have kitchen scales, one flat one that goes up 1kg and one that looks like this picture that ...
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1answer
236 views

Spontaneous Symmetry Breaking

In Spontaneous symmetry breaking we have got that, a field $$\phi= \pm \sqrt{\frac{-m^2}{\lambda}}.$$ Now in order to get the unstable minima we need to guess the mass $m^2 <0 $. But can mass be ...
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2answers
7k views

Energy & Mass of a Photon [duplicate]

$$\text{Please read the whole question before answering}$$ Before I ask my question, I would like to say that "Yes, I do know a photon has no mass." I was helping someone here on P.SE with the ...
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4answers
484 views

Since everything with mass exerts a gravity force on everything else, why do objects float in outer space?

For example, if you were to go out into deep space, and just slow down and stop your rocket. Everything inside the rocket that's not strapped in, starts floating. Why is that if every object has mass ...
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1answer
210 views

Do massive particles exchange Higgs bosons?

Do massive particles exchange virtual Higgs bosons between themselves? If they do does the resulting Higgs force decay exponentially with distance?
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6answers
13k views

Which way does the scale tip?

I found the problem described in the attached picture on the internet. In the comment sections there were two opposing solutions. So it made me wonder which of those would be the actual solution. So ...
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8answers
99k views

If photons have no mass, how can they have momentum?

As an explanation of why a large gravitational field (such as a black hole) can bend light, I have heard that light has momentum. This is given as a solution to the problem of only massive objects ...
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2answers
459 views

Photons have no mass. So, why does $E = pc$ hold? [duplicate]

It's a somewhat theoretical question. In special relativity, The energy of a photon is given by $E = pc$. But, my argument is that, since photons have no mass, how can they have a momentum $p$? The ...
3
votes
1answer
83 views

How do gauginos and scalars gain masses after gauge-mediated symmetry breaking?

In the minimal-GMSB model, the messenger fields transform under the MSSM gauge group and connect a so-called hidden sector to the visible sector. These meesenger fields (left-handed chiral ...
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4answers
554 views

Mass-Energy relation

Einstein mass- energy relation states $E=mc^2$. It means if energy of a paricle increases then mass also increases or vice-versa. My question is that what is the actual meaning of the statement "...
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1answer
95 views

Significance of angle in relativistic mass equation

I was playing with $$M=\frac{m_0}{\sqrt{1-v^2/c^2}}$$ and when I put $v=c\sin\theta$, I got $$M=m_0\sec\theta.$$ And this new equation is appearing so beautiful and attracting to me that I was ...
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1answer
192 views

The FRW universe is NOT asymptotically flat? Its mass?

The Friedman-Robertson-Walker (FRW) metric in the comoving coordinates $(t,r,\theta,\varphi)$ which describes a homogeneous and isotropic universe is $$ ds^2\,= -dt^2+\frac{a(t)^2}{1-kr^2}\,dr^2 + a(...
3
votes
1answer
88 views

Glashow-Weinberg-Salam mass terms

At the end of spontaneous symmetry breaking I get these mass terms: $$W_{\mu}^{\pm}=\frac{1}{\sqrt{2}}\bigl(W_{\mu}^{1} \mp i W_{\mu}^{2} \bigr )$$ $$\mathcal{L}_{mass}=\frac{1}{2} g^2 \frac{v^2}{4} ...
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1answer
193 views

Reduced mass and harmonic mean

In two-body problems, a reduced mass has the form: $\frac{m_1 m_2}{m_1+m_2}$, which by appearance, is half of the harmonic mean of $m_1$ and $m_2$: $\displaystyle\frac{2}{\frac{1}{m_1}+\frac{1}{m_2}...
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votes
2answers
510 views

How can gravity affect light?

I understand that a black hole bends the fabric of space time to a point that no object can escape. I understand that light travels in a straight line along spacetime unless distorted by gravity. If ...
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2answers
358 views

What is the meaning of negative mass (in a SUSY spectrum)?

I was playing around with SuSpect to generate some SUSY mass spectrums and I'm often encountering situations where I get a negative neutralino mass. What is the physical meaning of this negative ...
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2answers
635 views

Is light affected by gravity? Why?

I would like to know if light is affected by gravity, also, I would like to know what is the correct definition of gravity: "A force that attracts bodies with mass" or "a force that attracts bodies ...
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1answer
98 views

Could the center of the combined mass of the entire galaxy change if there were no external forces acting on that galaxy?

Everything in the galaxy orbits the center of the combined mass of the entire galaxy. So could the center of the combined mass of the entire galaxy change if there were no external forces acting on ...
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votes
5answers
3k views

Is mass an observable in Quantum Mechanics?

One of the postulates of QM mechanics is that any observable is described mathematically by a hermitian linear operator. I suppose that an observable means a quantity that can be measured. The mass ...
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votes
2answers
97 views

Discrepancy ( or Confusion ) in the mass of photon

$E$ = $mc^2$ And also $E$ = $hf$ (f - frequency) And hence Einstein said $m$ = $hf\over c^2$ And so photons have mass But later he also said $M$ = $M_0\over \sqrt {1-v^2/c^2}$ Where if we put $v ...
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1answer
827 views

How muscle force work? [closed]

If muscle works with force on joint and joint works with exact force on muscle(newton III law) how can muscle drag much heavier weight than itself?
2
votes
3answers
117 views

Finding the mass of pure matter [closed]

How would I find the mass of "pure" matter, that is, non-quantized matter, for a given volume?Let's say I have a volume equal to 1 meter squared, and I completely filled it up with matter - that is, ...
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1answer
574 views

Coupled Spring System (3 mass 3 springs)

Hello I am having trouble trying to find the correct model for this coupled spring system. The scenario is the following we have: Ceiling - Spring - Mass(1) - Spring(2) - Mass(2) - Spring (3) - Mass(3)...
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2answers
3k views

What is the optimal weight for a golf ball?

I am 32 now, and have forgotten the basic physics formulas we used in school. I am sitting with a question that is bugging me. If I had to hit two golf balls of different weight with the same force, ...
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2answers
159 views

Higgs field and masses of particles

Interaction of particle with Higgs field provides mass to the particles, then why still some particles are massless?