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.
2
votes
1answer
202 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 ...
13
votes
9answers
1k views
What is the difference between weight and mass?
My science teacher is always saying the words "weight of an object" and "mass of an object," but then my physics book (that I read on my own) tells me completely different definitions from the way ...
4
votes
4answers
303 views
Relativistic mass and imaginary mass
The (relativistic) mass of an object measured by an observer in the $xyz$-frame is given by
$$m = \frac{m_{rest}}{\sqrt{1 - \left(\frac{v}{c}\right)^2}}.$$
Mathematically $v$ could be greater than the ...
3
votes
2answers
279 views
Matter waves - DeBroglie's relations
I am currently studying from Modern Physics for Scientists and Engineers by Taylor et al. They derive the DeBroglie relation $p=h/\lambda$ from setting mass $m=0$ in the energy-momentum relation ...
6
votes
3answers
260 views
What is the massless limit of massive electromagnetism?
Consider electromagnetism, an abelian gauge theory, with a massive photon. Is the massless limit equal to electromagnetism? What does it happen at the quantum level with the extra degree of freedom? ...
0
votes
1answer
82 views
Why the kilogram is not defined? [duplicate]
Possible Duplicate:
Why do we still not have an exact definition for a kilogram?
I was thinking about SI units. I found the following definition for the base units:
Meter: distance ...
0
votes
2answers
208 views
Center of mass of a car
This might be little of the track but my question is more on possibility of application of principle of center of mass.
The probability of a vehicle overturning depends more on the level of center of ...
0
votes
0answers
32 views
Could the quantity mass in the whole galaxies decrease to zero if all particle in the galaxies convert into subatomic particle? [closed]
Could the quantity mass in the whole galaxies decrease to zero if all particle in the galaxies convert into subatomic particle?
How does your statement work?
0
votes
0answers
121 views
Neutrino mass with Dirac and Majorana
Why both Dirac mass and Majorana mass terms are needed to explain the mass of a neutrino?
1
vote
3answers
111 views
Does Earth's rotation change at a constant rate?
Follow-up to
Is Earth's orbit altered by recoil from take-off/launch/recovery of aero/space vehicles? and
How much meteoric/space dust does the moon accumulate daily?
Is the length of the day ...
0
votes
1answer
67 views
How much meteoric/space dust does the moon accumulate daily?
Just what the title states.
Any body, as it travels through space, probably sweeps meteoric/general dust from the vicinity into itself. How much (in tons/kilograms) dust does the moon accumulate ...
-1
votes
1answer
89 views
Why is the lightness of particles remarkable?
Why is the lightness of particles unexpected?
http://motls.blogspot.com/2012/09/experimenters-susy-frustrations-and.html
1
vote
1answer
138 views
Is $w=mg$ the right way to calculate mass?
How can you find the mass of an object by using a weight and a gravitational acceleration from another planet then earth? I was given $5.8\text{ N}$ and an acceleration of $4.0\ \mathrm{m/s^2}$. The ...
2
votes
4answers
350 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.
0
votes
1answer
53 views
Non-conversion of mass & energy?
This article is certainly an interesting alternative perspective, but is it factual or does it contain fallacies?
http://www.circlon-theory.com/HTML/EmcFallacies.html
Are mass and energy not ...
5
votes
3answers
371 views
What is the mass of a wave?
The slide called "QUANTA" here says that "One Quantum has a definite mass" and the picture shows a wave. So, What is meant by the mass of a wave?
3
votes
3answers
595 views
Is there a finite amount of mass in the universe?
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 ...
5
votes
2answers
162 views
Why would a particle in an extra dimension appear not as one particle, but a set of particles?
I was reading an article in this months issue of Physics World magazine on the three main theories of extra dimensions and stumbled across something I didn't quite understand when the author began ...
4
votes
1answer
70 views
How can we have massive states of strings and CFT on the string worldsheet at the same time?
Ok, so we can have conformal invariance on a string world sheet. However, it is well known that to preserve conformal symmetry we require states to be massless. So how is it that string theories ...
0
votes
0answers
63 views
Converting $q/m_e$ to $C/kg$ [closed]
I was doing some chemistry problems when I came across a question asking to find the charge to mass ratio of an electron in $q/m_e$. Then, it told me to compare what I found to the accepted value, at ...
0
votes
2answers
2k views
Why do objects with different masses fall at the same rate? [duplicate]
Possible Duplicate:
Confused about the role of mass
Today we were in our Literature class talking about the Renaissance and the Enlightement and our teacher also said that scientific ...
1
vote
1answer
181 views
What gives matter Gravitational Mass? [duplicate]
Possible Duplicate:
Does the equivalence between inertial and gravitational mass imply anything about the Higgs mechanism?
In Higgs mechanism, Higgs field, which likes syrup, slows down ...
0
votes
2answers
715 views
Preventing a block from sliding on a frictionless inclined plane
I want to demonstrate what force $F$ you would have to exert on an inclined plane of angle $t$, mass $M$ to prevent a block on top of it with mass $m$ from sliding up or down the ramp. I worked out ...
1
vote
2answers
131 views
The physics behind The Great Flood [closed]
The book of Genesis floats (pardon the pun) some interesting numbers when discussing the Great Flood. For example, it rained for 40 days and 40 nights, and at the end of that time, the entire planet ...
7
votes
2answers
926 views
'Density' of a proton
I was doing some exercises the other day, when I came across this question in my book:
A proton weighs about 1.66 x 10-24 g and has a diameter of
about 10-15 m. What is its density in g/cm3?
...
1
vote
1answer
115 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 ...
-4
votes
3answers
117 views
How to recognize broken candies from whole ones [closed]
Let's say I have a bag full of sugar candy. Some will be whole, some will be dent, some will be broken (in part, or half, etc).
Let's say I have a device with an input box where I empty the bag, and ...
1
vote
2answers
244 views
Why do photons add mass to a black hole?
Why do photons add mass to a black hole?
When photons are taken irreversibly into a black hole does the mass of the BH increase?
10
votes
1answer
558 views
Does the mass of a battery's change when charged/discharged?
... and if so, how much? Is it possible to detect it, or is it beyond any measurement? I'd say there are two possible scenarios (depending on the battery type) and both seem interesting:
The battery ...
0
votes
3answers
951 views
How is light affected by gravity?
Light is clearly affected by gravity, just think about a black hole, but light supposedly has no mass and gravity only affects objects with mass.
On the other hand, if light does have mass then ...
6
votes
3answers
412 views
How are the masses of unstable elementary particles measured?
I am interested in knowing how (Q1) the particle's masses are experimentally determined from accelerator observations.
What kind of particles? They must be as far as we know elementary and unstable ...
4
votes
2answers
201 views
Negative Mass and gravitation
Since Newtonian gravity is analogous to electrostatics shouldn't there be something called negative mass? Also, a moving charge generates electric field, but why doesn't a moving mass generate some ...
0
votes
1answer
162 views
Expression for the (relativistic) mass of the photon [closed]
I started learning a bit ahead from an old physics book, and they were discussing the photoelectric effect and after that Planck's hypotheses and energy quantas.
The book said that the mass of a ...
1
vote
2answers
161 views
Why does the (relativistic) mass change & why?
I studied that when an object moves with a velocity comparable to the velocity of light the (relativistic) mass changes...but I am really eager to know how does this alteration take place....If anyone ...
3
votes
3answers
147 views
Charge Analog of the Higgs Boson?
Since mass can be given to particles via the interaction with the Higgs Field could there be a "Charger Field" that supplies particles with charge? Possibly this would require two different "charger ...
2
votes
3answers
286 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 ...
0
votes
2answers
163 views
Why equivalence principle is principle and not law?
We can prove that the inertial mass and the gravitational mass should be the same (equivalence principle) from the $f=mg=ma$ then $g=a$, so we have equivalence law! But why we said equivalence ...
1
vote
2answers
411 views
Free fall of two spheres made of same materials, different masses, with air resistance
Two people falling with the same parachute will gain different speeds if their masses are different. The upward air drag will needed to be bigger for a heavier person, since gravitational force is ...
0
votes
0answers
37 views
What gives photons their energy? [duplicate]
Possible Duplicate:
Does $E = mc^2$ apply to photons?
I've been to a presentation by a CERN scientist, and he briefly talked about photons. It was stated that photons have different energy ...
0
votes
1answer
59 views
Is mass of the parent star is equal to the mass of the born blackhole
I want to know whether mass of the black hole which has born from a star is similar to its parent star or not. whether the born black hole will have high or low mass comparing to its parent star. ...
1
vote
1answer
616 views
Calculate mass of air in a tyre from pressure
How can one calculate the mass of air inside a tyre, given a particular tyre size; a pressure, in $kPa = \frac{1000kg}{m\cdot s^2}$; and assuming room temperature, and normal air composition? I can't ...
4
votes
3answers
249 views
How come a photon acts like it has mass in a superconducting field?
I've heard the Higgs mechanism explained as analogous to the reason that a photon acts like it has mass in a superconducting field. However, that's not too helpful if I don't understand the latter. ...
1
vote
2answers
127 views
Do particles gain mass only at energy levels found during the big bang?
I am trying to make sure my understanding is correct.
At energies and temperatures found during the big bang (or at CERN recently), the Higgs mechanism comes into effect. When it does, there is a ...
1
vote
1answer
116 views
Lepton masses in the Standard Model
Some simple questions regarding leptonic masses in the Standard Model (SM):
Why there is not an explicit mass term in addition to the effective mass term that arises from the Yukawa terms after ...
0
votes
2answers
204 views
Does the potential energy related to a particle determines its rest mass?
Would it be possible to determine the rest mass of a particle by computing the potential energy related to the presence (existence) of the particle, if this potential energy could be determined ...
3
votes
2answers
411 views
What sort of “mass” is explained by the Higgs mechanism?
When I asked this question (probably in a less neutral form) to physicists, their answer was something along the lines that it's not gravity (i.e. unrelated to gravitons) but inertial mass. (So I ...
2
votes
5answers
959 views
Why Gravity attracts all objects with the same speed?
Why Gravity attracts all objects with the same speed? Is this question was solved? What is the exact answer?
1
vote
1answer
92 views
Are there any well-known theories successfully unifying the inertial and gravitational mass?
From what little I know of general relativity, the equality of inertial and gravitational mass is an axiom of the theory. I suspect that this precludes GR from unifying them in the same sense as ...
3
votes
2answers
226 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? ...
-1
votes
3answers
462 views
Relation between Newtons and Kilograms
Work is expressed as W=F*d, where the F is in Newton, d is in meters and result ...
