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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911 views

Calculate stainless steel pole necking limit

Background Trying to determine how much weight a post can support without necking when a monitor is attached to an articulated arm: a cantilever problem. Problem There are three objects involved in ...
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1answer
86 views

Why doesn't a wall move when you push it if there's space behind it?

In the first screen you can see that if a person were to push a wall within a typical household the wall would not move while keeping themselves tractioned to the floor. If you push hard and do not ...
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216 views

What the heck is negative effective mass?

I am reading this book:Solid State Electronic Devices by Ben G Streetman and Sanjay Kumar Banerjee. I have some doubts in the article 3.2.2 Effective mass. In this the aythors say that ...
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1answer
150 views

Effective mass of a black hole?

Suppose a black hole forms from a given mass of particles such as the core of a star going supernova. The black hole formed will have an effective mass due to the curvature of space time induced. Such ...
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2answers
434 views

Does the Chandrasekhar Limit scale for a Black Hole?

No physicist/astrophysicist I; All I know about the Chandrasekhar limit is that it apparently limits the mass a star may survive, beyond which it degenerates to a neutron star, or a black-hole. Does ...
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49 views

Asymtotically flat spacetime applicable for spacetimes which are not diffeomorphic to $\mathbb{R}^4$

I wanted to investigate changes on a compact 4-manifold $M$. More specifically it is the K3-surface. I follow a paper by Asselmeyer-Maluga from 2012. The idea there was to make sure that the manifold ...
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49 views

Current known *lower* bounds to the neutrino masses?

I started a little bit of Googling around the topic, and found very few information. There are mainly upper limits. I found lower limits only to the rest mass differences of the different neutrino ...
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0answers
33 views

Classic mass predictions from Left-Right models with discrete symmetries?

I am covering the classic literature on predictions of Cabibbo angle or other relationships in the mass matrix. As you may remember, this research was a rage in the late seventies, after noticing that ...
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5answers
848 views

Planck mass is about the mass of one eyebrow hair

Unlike most Planck units named after "Planck" such as Planck length, Planck temperature, etc, the Planck mass seems more closed to daily life. It is about $10^{-5}$g, same order of magnitude of one ...
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2k views

Is there a finite amount of mass in the universe? [duplicate]

So, I'm not too physics savvy but I am curious to ask. Is there a finite amount of mass in the universe? or is there more and more being created from somewhere or something? If the universe is ...
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2answers
260 views

Do photons have mass? [duplicate]

As a student in a highschool physics class, my teacher has repeatedly told me that photons are massless. Yet, I have also heard from other sources that photons have momentum. If photons were to have ...
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4answers
452 views

Does $p=mc$ hold for photons?

Known that $E=hf$, $p=hf/c=h/\lambda$, then if $p=mc$, where $m$ is the (relativistic) mass, then $E=mc^2$ follows directly as an algebraic fact. Is this the case?
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4answers
169 views

What is difference between Inertial mass and gravitational mass [duplicate]

I recently read that the mass we deal with in Equation $F=Ma$ is called inertial mass and the mass we deal with in $F=Mg$ is gravitational mass. Suppose I am taking a same ball in a free fall and in ...
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3answers
335 views

Is a spinning object heavier than a non-spinning object?

Does spinning an object make it heavier? A real-world example: I was mowing the lawn in front of my house, a lawn that tends to have some steep inclines. I realized that the lawn-mower was easier ...
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2answers
6k views

Do light and sound waves have mass

I have been reading Hawking's 'A Brief History of Time' and it has gotten me thinking about Einstein's theory of relativity, in that it assumes that an object must have infinite mass if it is to be ...
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3answers
2k views

Is it possible to calculate weight of person with sensors found in today's smartphone?

Is it possible to calculate the weight of a person by only using his smartphone, some action he must perform (jump, rotate etc.) and some data like his height or age. Current smartphones have the ...
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4answers
99 views

What would the gravity be like if Earth and the moon were touching?

What would the gravity be like if Earth and the moon were touching? Assuming the moon keeps its form and doesn't collapse on its own weight, would the area between it and the Earth (point B) have ...
3
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2answers
378 views

Why are particles different sizes?

Is it correct in saying that a particles size is it's rest energy, and that particles don't actually have size (in the way you get different size objects)? What defines what sizes a particle can be? ...
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3answers
484 views

What does “nearly infinite mass” mean?

I am sure this is a silly question, but I was reading something that described the pre big-bang universe as having "nearly infinite mass." How can something be "nearly" infinite? The term seems to ...
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3answers
242 views

Can a mass matrix be asymmetric?

I am developing a mathematical model of a mechanical device consisting basically of coupled harmonic oscillators. It turns out that the system mass matrix is asymmetric. I seem to read somewhere that ...
3
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2answers
1k views

Higgs-Boson/Graviton [duplicate]

The Higgs boson gives particles mass. And the graviton is the theoretical force-carrier of gravity. Gravity depends on mass. So if the Higgs Boson gives things mass, it therefore gives them gravity. ...
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4answers
990 views

Do we say that phonon has effective mass through its dispersion relation?

The effective mass is proportional to the second derivative of the dispersion relation d2k/dE2. Do we say that phonon have effective mass through it ? Spin wave have.
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3answers
873 views

Does a toy top weigh less when it is spinning?

I am under the understanding that a toy top will weigh less when it is spinning. The Russians made a spinning type transport back in the 70s to lessen its payload over the tundra. Is this an effective ...
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1answer
229 views

Does string theory pose a photon mass problem?

A few weeks ago, I started reading books on string theory. One thing that really seemed confusing or contradictory was that string theory explains that the energy of a superstring gives mass to the ...
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2answers
2k views

Orbital speed for a circular orbit?

I wanted to look up the formula for orbital speed for a circular orbit on Wikipedia, and I found 2 formulas: All bounded orbits where the gravity of a central body dominates are elliptical in ...
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1answer
209 views

Photon mass and life time

In this article, the author tried to explain that, Einstein's theory may not valid because he says "photon can decay because it may have minute amount of mass". I'm totally in a conundrum state that ...
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182 views

Strings and their masses

How do strings present in particles give mass to them? Is it only by vibrating? I have been trying to find the answer but could not find it anywhere, can this question be answered?
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3answers
6k views

All matter has a mass but does all matter have a gravitational pull?

I know that all planets and stars have a gravitational pull but does a simple much smaller object have a gravitational pull for example a pebble?
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4answers
340 views

Electromagnetic factors affecting inertial mass of a body affect its gravitational mass or not?

We can see that when a charge sphere is at rest & we are to put it in motion with any desired velocity than we will have to apply the same force for a longer time as if it were applied to the ...
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2answers
137 views

How can we get the mass of an uncharged proton?

How can we get the mass of an uncharged proton, i.e. how varies the mass of the charged proton if i remove the electric charge? For the isotopic spin theory neutron and proton have the same mass and ...
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2answers
5k views

Does a scale measure weight or mass? [closed]

What does a measuring scale measure: mass or weight? I mean, when we stand on a weighing scale the reading we get is in $\mathrm{kg}$'s. What does this mean?
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1answer
396 views

Have negative pressures any physical meaning?

Some cubic thermodynamical equations of state predict negative pressures, have negative pressures any physical meaning? Could they be related to negative mass?
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2answers
1k views

First and Second Moment of Mass

I recently came across the definition of the Center of Mass of a system as the point about which the first moment of mass is zero. Further, it defined Moment of Inertia as the second moment of mass. ...
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1answer
607 views

What bends fabric of space-time?

I know that mass can bend fabric of space-time, which causes gravity by making an object curve around a planet or star but is there anything else that can bend it? Other energy sources, forces ...
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295 views

Dropping cubes of same masses but different sizes?

Two cubes of the same mass but different sizes (smaller Cube A and bigger Cube B) are dropped from same height on to a tray of sand.Which cube will create a deeper impression and why?
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1answer
117 views

How much weight can a person carry to avoid being blown over by wind?

I wonder if there is a certain amount of weight that I could carry in a rolling bag to help prevent me from being knocked over by the wind. I have balance problems and some lack of muscle strength in ...
3
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1answer
177 views

Why is Planck mass much larger than the smallest mass that we actually know about?

The three fundamental constants $h$, $c$ and $G$ are manipulated and rearranged in different ways to get the Planck time, Planck mass etc. The Planck time is said to be the smallest time possible and ...
3
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1answer
132 views

Topological Mass Generation Mechanism

What is the topological mass generation mechanism? And what is its relation with the Higgs mechanism? Can we say that after the discovery of Higgs boson, the topological mass generation mechanism ...
3
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1answer
2k views

Terminal velocity of two equally shaped/sized objects with different weights?

I've tried doing research on this and there are some similar questions. However, they have slightly different scenarios and to make sure I understand things perfectly, I wanted to word it into my ...
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2answers
146 views

Gravitational distortion of an object's diameter, at a distance,

Does the curvature of space-time cause objects to look smaller than they really are? What is the relationship between the optical distortion and the mass of the objects?
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2answers
4k views

Modeling a two-mass, spring, damper system

I'm trying to model a system with two masses, two springs, two dampers, and one applied force using transfer functions. I'll then be inputting it into Simulink. The system looks like this but there ...
3
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1answer
319 views

Difference between baryonic, inertial and gravitational mass? (and relation to dark matter)

Inertial mass: determined from Newton's f = ma Gravitational mass: determined via Newton's law of gravity Baryonic mass: sum of mass of all baryons. Which ones ...
3
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3answers
410 views

storing energy (as mass)

When chemical energy is released mass is reduced, if only by a negligible amount. Presumably that's true for all energy. And presumably that works in reverse as well: storing energy involves an ...
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3answers
2k views

Mass of particle near light speed in a medium

I am trying to get a common understanding from these two previous questions: Why does the mass of an object increase when its speed approaches that of light? What happens if light/particles exceeded ...
3
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1answer
46 views

Photon Mass Term in Schwinger's 2D QED Model

Why does the vacuum polarization in 2D massless Fermion QED, $$ i\Pi^{\mu\nu}(q) = i(\eta^{\mu\nu}-\frac{q^\mu q^\nu}{q^2})\frac{e^2}{\pi}, $$ have the structure of a photon mass term, as is ...
3
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2answers
294 views

Determination of mass density distribution of an object

This is a follow-up to a previous question How can you weigh your own head in an accurate way?. My purpose is not to restart the flurry of more or less humorous jokes (which are not such a bad thing ...
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1answer
264 views

An atomic bomb explodes inside of an “unbreakable” container which is on a scale. Does the “weight” of the container change?

This may or may not be an incredibly stupid thought experiment, but a short time ago I read that most of the "mass" in the proton was actually energy from the quarks and gluons, as opposed to the ...
3
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4answers
9k views

Relationship between mass, energy, and a force?

I've never truly understood the relationship between mass, energy, and force. I know what each of the three are, I just don't fully understand how they interact with each other. For example, How ...
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2answers
583 views

Where does the mass term come from in the Proca Lagrangian?

There are many good books describing how to construct the Lagrangian for an electromagnetic field in a medium. $$ \mathcal{L}~=~-\frac{1}{16\pi}F^{\mu\nu}F_{\mu\nu}-\frac{1}{c}j^{\nu}A_{\nu} $$ ...
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1answer
354 views

Does the Photino have mass or is it mass-less like the photon

Does the photino in super-symmetry have a mass, Or is this different in different super symmetric models?