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If you care about the inertia you use "mass". When you are considering the force of gravity you use "weight". So when you do calculations about the force in the cables due to acceleration of an elevator car you need to know both it's mass and it's weight... The (calibrated) object you place on a scale is called a "weight" - because that is the property you ...


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We use the term mass, when we mean the mass of a weight, and we use the term weight, when we mean the weight of a mass. :-) The important thing to remember is, that the mass is the same everywhere, while the weight varies with the local gravity. So if you are referring to the constant mass of an object, you use mass expressed in kg. If, however, you mean ...


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See the standard text by Peter J. Brockwell & Richard A. Davis "Time Series:Theory and Methods" 2 ed, p.331, where authors define $\omega_j=2\pi j/n\in(-\pi,\pi]$ (integer multiples of the fundamental frequency $2\pi /n$) as Fourier frequencies. Later on p.335, they say "if $\omega$ is not a Fourier frequency, the analysis is a little more ...


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The SIS accelerators are heavy ion accelerators, and the German for heavy ion accelerator is SchwerIonenSynchrotron (my capitalisation), hence the abbreviation SIS. There is more info in this article.


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SIS-100/ SIS-300 is an accelerator under construction for FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. see - http://cern.ch/AccelConf/e08/papers/mopc100.pdf I believe, but am not sure, that the -100 and -300 refers to the magnetic rigidity (i.e. Magnetic field * bending radius) of the accelerators, which determines the maximum ...


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The sort of trick involved in removing the $|P\rangle$ on both sides to get the conjugate imaginary equation $$\langle P|\xi|P\rangle = \langle P|a|P\rangle \tag1 $$ is quite common but it is indeed nontrivial to grasp the first time. In essence, you leverage the fact that in an equation of the form $$ ⟨\psi|\hat A|\phi⟩=⟨\psi|\hat B|\phi⟩\tag2 ...


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I know that air pressure and temperature are inversely proportional. You should not know that. This is the source of your misunderstanding. The ideal gas law, $PV=nRT$, can be rewritten as $P=\frac R m \rho T$, where $m$ is the average mass of a molecule in the gas and $\rho$ is the density of the gas. The first term on the right is a constant for a ...


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Here's a point of view from thermodynamics that might be useful. Typically, the intensive quantities (in the form they're usually defined) arise as derivatives of the total (internal) energy $U$ by some particular extensive quantity. Thus: Temperature $T=\frac{\partial U}{\partial S}$, the derivative with respect to the entropy Pressure $P=-\frac{\partial ...


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This is a very interesting question. Velocity can be considered as either an intensive or an extensive property, depending on whether we are inquiring about the parts of a single system, or considering relations among separate systems. Velocity must be an intensive property, for consider: If I and my passenger and my books are traveling in my car, and if ...


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1)Yes sedimentation velocity is terminal velocity. 2)No, Not necessarily. Buoyancy Depends on the Volume of water displace by the object where as gravitational force is weight of object. Let us look at 2 cases here: Constant values: g, Gravitational acceleration = 10 m/s2 d, Density of water = 103 Kg m3 CASE I: V, Volume=103 m3 D, Density object= 103 ...


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The best way to understand the nature of intensive and extensive quantities in thermodynamics is like this: Take a system of your interest. Make it into two portions (one large portion and the other a small portion) by using a partition, for example. Then see the property of interest of the two samples. Density of the two portions will be the same as the ...


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The web site you link is using the expression: $$ \rho_c = \frac{3}{8\pi G \theta^2} $$ where $\theta$ is the Hubble time and is equal to $1/H$. So your second equation should be: $$ \rho_c = \frac{3}{8\pi G \theta^2} = \frac{3}{8\pi G \left(1/H\right)^2} = \frac{3H^2}{8\pi G} $$


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Hints: The action is $$\tag{A} S[y]:=\int_0^1 \! dt ~L(y,\dot{y}), \qquad L(y,\dot{y})~:=~\frac{m}{2}\dot{y}^2 -mgy, $$ with Dirichlet boundary conditions $$\tag{B} y(0)~=~0 \quad\text{and}\quad y(1)~=~-\frac{g}{2}. $$ Calculate explicitly the composed function $$\tag{C} s(\epsilon)~:=~ S[y_{\epsilon}] , $$ where $$\tag{D} ...


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I've tracked a variety of quasiparticle issues for over 20 years now, including a couple of deep literature dives on fractionally charged topological solitons in materials such as polyacetylene. The term quasiparticle has always dominated in the articles I've found. That's true even for integer spin excitations, which after all are quite particle-like in ...


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1. No, there is no "shift in meaning". "Accuracy", "precision", and "trueness" is a technical term for measurement not physics. And there is no such thing as a "measurement community" because measurement occurs everywhere. As such, "accuracy", "precision", and "trueness" are heavily overloaded technical terms used in varying fields like maths, computer ...


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Yes, the term "shadow" can refer also to something or (dare I say) someone that is dark, shady, inconspicuous, etc. One can also use it as a verb; to shadow someone is to follow them closely. Like "I'm having the new guy shadow me for a while until he learns how to do everything".


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Yes! Any beam that is blocked by an object will basically make a shadow. For example, the IceCube detector can see the moon's cosmic ray shadow.


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Yes, for example a Crookes tube shows an electron shadow. The area I live (Chester, UK) is in a rain shadow.


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For example, acoustic shadow (http://en.wikipedia.org/wiki/Acoustic_shadow ).


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In the equation (i.e. mathematically), where do you see the differences between continuity equations and conservation laws? The continuity equation is not sufficient to derive conservation of something. For example, continuity equation for fluid flow in non-relativistic theory is $$ \partial_t \rho + \nabla \cdot (\rho \mathbf v) = 0 $$ wherer $\rho$ ...


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Continuity equations are an embodiment of local conservation laws, and they both reflect the fact that there is no 'quantity teleportation'. That said, the local transport of a quantity is perfectly possible within local conservation laws and it is precisely this that the continuity equation models. Your distinction between global and local conservation ...



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