the definition of mass

[studiot]

I really think that the reference I gave in post#12 explaining inertial mass is most elegant and accessible.

 

In pages 1 -6 Kermode provides a wonderfully chatty exposition of introductory mechanics, including simple versions of Newton's laws (N1;N2:N3) along with a good explanation of why it can be misleading to say simply

 

"force is proportional to acceleration, the constant being mass"

 

His description of the broken railway coupling, designed by a designer who believed this, is a prime example.

 

It may be noted that Kermode taught practical people (pilots) who need an intuitive but practical understanding of mechanics, rather than the ability to manipulate mathematical formulae.

Edited May 6, 2013 by studiot

[ajb]

I really think that the reference I gave in post#12 explaining inertial mass is most elegant and accessible.

I have never come across the book The Mechanics of Flight by A.C. Kermode, so I cannot comment at all on the description he gives. Though it is clear that one has to be careful with F=ma.

What's the mass of a quark?

Okay, so here we are in the domain of quantum field theory and one has to be careful with what you mean by the mass. You have two common meanings for the mass of a quark

• current quark mass; the mass of a bare quark.
• constituent quark mass; the current quark mass plus the mass of the gluon particle field surrounding the quark.

To muddy the waters even more, we have the notion of the physical mass in perturbative quantum field theory as the location of the pole of a propagator. Edited May 8, 2013 by ajb

[Stasis]

In short,
mass is the measure of inertia of a body and the constant of proportionality between force and acceleration...

[EdEarl]

The universe is 99.99...9% empty.

 

And, whatever isn't empty, spontaneously created from nothing almost 14 billion years ago in the BB, which wasn't a bang; rather, it was the expansion of an infinitely small point, which is expanding into infinity.

 

I think the best answer to "What is mass?" and "What is the definition of mass." is that it is a quality of matter.

However, we really do not know what matter and energy are. The theory of everything is incomplete...maybe not even started.

 

Moreover, I am confused about whether this thread should be in physics, phylosophy, or speculation.

Edited May 15, 2013 by EdEarl

[ajb]

mass is the measure of inertia of a body and the constant of proportionality between force and acceleration...

Right, that is the inertial mass.

 

Moreover, I am confused about whether this thread should be in physics, phylosophy, or speculation.

If we stick to the defintions of mass as used in physics and consider things that can be measured, directly of indirectly, then we are discussing physics.

[krash661]

here's something i came across a time ago,

 

mass

physics- physical quantity: the property of an object that is a measure of its inertia, the amount of matter it contains, and its influence in a gravitational field.

 

quantity

amount: an amount or number of something

physics- particular magnitude of something: the product of a measurable phenomenon such as electric current or radiation intensity and the time during which the phenomenon is measured

 

magnitude

greatness of size: greatness of size, volume, or extent

mathematics- number assigned to mathematical quantity: a numerical value that describes the amount of something, usually expressed in terms of a multiple of standard units, or the item measured in this way

 

dilation

expanding of something: the act or process of widening or being widened, enlarging or being enlarged, or stretching or being stretched

expanded condition: a condition in which something is widened, enlarged, or stretched

expanded thing: something, especially a part of something else, that has become widened, enlarged, or stretched

[krishnabharadwajr]

What is the definition of mass??

 

Mass of the body is the amount of matter it contains.

or simply it is the measure of inertia.