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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Moment of inertia and gravity

Would the objects have moment of Inertia if there was no gravity? Because imagine a bar, if I put my hand at the center of the bar and rotate it, it would be easier than rotate the bar picking one ...
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1answer
28 views

Net force equal to mass multiplied by acceleration of centre of mass [closed]

$F=ma$ if $a=0$ then definitely the net force applied will be also zero (0). then, in this case $m=F/a$. If both net force and acceleration(of centre of mass) is equal to zero (0). then, isn't mass ...
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2answers
83 views

What is more fundamental: Geometry and Topology or physical matter? [closed]

Since, there is always an interplay between gravity and the fabric of spacetime. I wonder which is more fundamental: Geometry and Topology or physical matter?
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2answers
955 views

How precise can current technologies measure the mass of an object?

Masses of various objects are listed on this wikipedia page: Orders of magnitude (mass). For example, mass of an HIV-1 virus is on the order of 1 femtogram. Are these data actually measured (which I ...
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47 views

I want to know about the quantization of mass [duplicate]

Is mass quantized? If yes, then why do we see all amounts of mass? Well , can it be said quantized just for smaller masses?
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3answers
93 views

What is the physical meaning of reduced mass?

If we stick two block masses by a string and pass it over a pully and let the blocks free then mathematically we can obtain that the whole weight on the pully is more if the blocks are kept at rest, ...
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0answers
21 views

Do all objects free fall at the same rate regardless of their mass? [duplicate]

Is it true that all object will fall at the same speed in vacuum irrespective of their mass because the acceleration due to gravity of Earth is 9.8 m/s2. Then what happens to the gravitational force ...
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3answers
4k views

Can something without mass exert a force?

I am something of a dilettante in physics, so please forgive me if the answer to this question is painfully obvious. The question is simple, can something that theoretically has no mass exert a force. ...
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4answers
177 views

How do we know the Schwarzschild solution contains an object of mass $M$?

The Schwarzschild metric is $$ds^2 = - \left( 1 - \frac{2GM}{r} \right) dt^2 + \left(1-\frac{2GM}{r}\right)^{-1} dr^2 + r^2 d\Omega^2.$$ In Carroll's GR book, it is claimed that $M$ is the mass of the ...
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18 views

Do greater mass objects attract objects quicker, than lessor mass objects? [duplicate]

If I jumped up and down on the moon it would take longer than if I jumped up and down on earth... the only changing variable being mass - the difference in mass between the earth and moon. wouldn't ...
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45 views

Force on a Massless String

Suppose we are just pulling a block with the help of a string which is massless. Now since the mass of the string is 0 the force exerted by us is transmitted without being diminished. So the equation ...
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1answer
57 views

Why is 1 kg of cotton heavier than 1 kg of stone? [closed]

I've been told that 1 kg of cotton has more density since Density = mass / volume, and volume of 1 kg of cotton is pretty big outside , and height of it very long, and stone is lighter because its ...
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2answers
43 views

How to calculate the maximum speed of an object?

There is a spaceship, whose mass is $100 \, \mathrm{kg}$. The thrust of its rocket is $300 \, \mathrm{N}$. How is it possible to calculate the maximal speed that the spaceship can reach, and the time ...
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0answers
28 views

How is mass of observable universe calculated? [duplicate]

How is even mass of earth known ? How do we get to know them? Whilst I was studying about dark matter it was listed about 'mass of observable universe' and density and so on...so what is the procedure?...
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3answers
49 views

Find the tension in each segment of rope suspending two hanging masses

I have the situation in the image where two masses are suspended along a piece of rope (resulting in three segments of rope). I need to find the tension in each of the three segments of rope. I know ...
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1answer
101 views

How did gravity exist before mass?

I'm brushing up on my Big Bang, and I noticed that, apparently, although gravity is the first force to split from the original "superforce", mass does not appear on the scene until after the second ...
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2answers
31 views

In Golf, What Influences More On How Far The Ball Travels?

Most of us are aware of the general concept that the harder you hit something, the farther it usually travels. (let us suppose we are neglecting any air resistance and friction that happens) And from ...
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1answer
97 views

Spinning a string with a mass on the end. What makes the mass rotate parallel to the ground? [closed]

Say you use your hand to rotate a string with a mass attached to the end. The string will first become taunt and then the mass and string will move upwards until they are spinning parallel to the ...
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3answers
162 views

Center of mass motion and variation of mass

Here are the proofs regarding the center of mass motion as reported on my book. $$\vec{r_{cm}}=\frac{\sum\vec{r_i} m_i}{\sum m_i}$$ $$\vec{v_{cm}}=\frac{d{\vec{r_{cm}}}}{dt}=\frac{1}{M}\sum \frac{d}{...
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0answers
67 views

Why is there no negative mass? [duplicate]

We know that the entire matter has a property called mass. Charge is also a property of matter. If negative charge can exist, why don't negative mass exist? Also, like charges repel each other. Then ...
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1answer
57 views

Distorting the space-time fabric

If point masses could be generated in a controlled manner distorting the fabric of space-time objects could be made to move in any direction relative to each other and not simply attract as is ...
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1answer
67 views

Force, Mass, Motion? $E = mc^2$

Does any object needs force to move? If 'yes', does the matter needs mass to form a force? These questions arises from me because $E = mc^2$ and $F = ma$ does not relate and one does not agrees with ...
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1answer
50 views

Force of baseball bat given force of ball and recoil distance

Say I swing a baseball bat and hit a ball. The ball is moving at 60 miles per hour and impacts the baseball bat squarely at that speed. The ball has moved twenty feet before impacting the bat. The ...
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1answer
22 views

Finding the force exerted by a mass at different contact points

Okay so I've been doing a math assignment on torque which has to have real-world applications so I've gone off on a massive tangent trying to incorporate physics principles and trying to get them as ...
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2answers
44 views

Quick question on weight/mass [duplicate]

(In the US, just to clarify)So, from a physics perspective weight and mass are different, but when people are talking about weight in everyday(non-physics) situations ("how much do you weigh" etc.), ...
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1answer
98 views

Does massive particle really move at speed of light? [closed]

According to this answer I understood that particles with mass also move at speed of light but interaction with higgs field make this movement zigzag. So average speed is below speed of light. But I ...
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1answer
42 views

Properties of a body with spherical symmetry

I'm studing Gauss law for gravitational field flux for a mass that has spherical symmetry. Maybe it is an obvious question but what are exactly the propreties of a spherical simmetric body? A ...
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5answers
197 views

Why do heavier objects fall faster on hills but not in straight drops?

All other things being equal, if a heavier object will roll at a higher speed down hill than a lighter one, because it's heavier with more mass, then how is it that dropped objects fall at the same ...
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0answers
46 views

Are the pions really all that light?

I'm studying the sigma model where the pions are identified as the (pseudo) Nambu-Goldstone bosons of chiral symmetry breaking ("pseudo" from mild isospin symmetry violation). This argument usually ...
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0answers
32 views

Helicity of massive particle at high enengy

We know that massless spin-1 particle like photon only has two helicity state (-1,1), what about the helicity of massive spin-1 particle (W boson) at very high energy? Does it have helicity 0 state ...
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2answers
123 views

Angular equilibrium on a see-saw

I have a tonne of questions related to see-saw equilibrium because most places I've been to online only deal with horizontal equilibrium - but static equilibrium can occur on an angle too. My ...
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1answer
91 views

Can you lift heavy objects in zero gravity? [closed]

I'm not someone who majored in physics and i never took the subject seriously when i was in school and im regretting that alot, there's so many things going in my mind that i cannot answer because i ...
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1answer
38 views

How is hemispherical shell any different from a semi-disc in terms of center of mass? [closed]

If we shift all the rings that make up the hemisphere parallel towards the center then it will build up two semi-disc .. But we know that We can also explain it by saying that if we take the shadow ...
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1answer
76 views

What is difference between 9.8 N (Kgwt) and 9.8 m/s^2 (g)?

What is difference between 9.8 N (Kgwt) and 9.8 m/s^2 (g)? What is difference between kg weight and gravity? I am not so good in physics so please explain in a lot of detail (but sorry for this silly ...
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3answers
89 views

Why charge is not a measure of inertia?

We know that mass is the measure of inertia of rest. Then why charge is not a measure of inertia? What causes the difference between charge and mass?
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3answers
204 views

Why is the definition of inertial mass circular?

On Wikipedia, the definition of inertial mass is: Inertial mass is the mass of an object measured by its resistance to acceleration. And, can be evaluated using $F = ma$, Newton's second law....
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1answer
192 views

How can the Higgs boson explain the inertia of the body?

We consider a thought experiment. Let weightless cylinder is located in the reference frame $K'$ (axis X, Y, Z). The height of the cylinder is equal to $h$ (Fig.1). The top cover of the cylinder is ...
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30 views

When space containing an extended mass contracts, what delivers or absorbs energy?

As my understanding goes, general relativity and the many theories that have sprung from it allow for the contraction and expansion of space. When such expanding (or contracting) space contains a ...
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39 views

What's the relation between representation theory and mass / electric charge?

This is a follow-up on this answer, where ACuriousMind wrote Formally, both the mass and the charge classify certain irreducible representations of the Poincaré group and the circle group, ...
3
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1answer
71 views

Rest Mass Clarification

I would like to know about the Rest Mass? Why we need the phrase "rest mass"? Because, mass is a constant quantity? Or Is the Mass varying with velocity? How can we understand that mass varying with ...
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3answers
80 views

Why do objects with mass have gravitational force that is proportional to their mass?

Why do objects with mass have gravitational force that is proportional to their mass, i.e the larger the object the more gravitational force it has?
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1answer
66 views

1-Loop Mass Splitting of vector-like Fermions

In this paper the author argues that for a vector-like fermion doublet, with degenerate mass $M$ at tree level, we always have a mass splitting between the charged component of the doublet $L$ and the ...
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1answer
32 views

Gyroscope is not in center of the mass

I have a controller with a MEMS gyroscope on it. Is there any difference if I put gyroscope not in center of the mass? Will be gyroscope drift increase?
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1answer
87 views

Deriving a Schwarzschild radius using relativistic mass

Introduction I have shown below two different approaches to deriving the Schwarzschild radius. I know these are less rigorous than the derivation of the Schwarzschild solution however the $\frac{2GM}...
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2answers
68 views

Are the properties assigned to quarks meaningful?

Suspect this may have been asked before, but can't find it. My question is: If you can never have a free quark, what sense does it make to attribute properties to them, since you can never ...
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0answers
31 views

Superstring mass between 2 D-branes

The mass of a superstring between 2 parallel D-branes of dimension $p$ and $q$ is $$m^2=(N−a)+(y/2π)^2$$ But what is the value of the normal ordering constant $a$?
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39 views

Is there a relation between time dilation and (relativistic) mass increase?

I noticed that what once called relativistic mass increase and now is called energy increase is ruled by the same formula the Lorenz factor of time dilation? The formula is too particular to suggest ...
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4answers
2k views

How do astronauts measure weight/mass on other planets? [closed]

At the start of The Martian movie the astronauts collect samples, targeting for "100 grams". Hence the question ... what units do astronauts actually use? I did some quick google search but all I get ...
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70 views

If two objects have the same drag coefficient, but one is much heavier, would it fall faster?

Not sure this is a good example but imagine we have two feathers, both with exactly the same drag coefficient, they have the exact same shape and everything, but the only difference is that one of ...
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33 views

Does vehicle tire mass effect efficiency?

This question has an interesting origin: A tire salesman was recommending tires (aka tyres) for a highly fuel-efficient vehicle. He said the vehicle was light (compared to most production cars), and ...