Physical Definition and 1000 Threads

Hello there, I have a confusion between dimensions and units! All of others tell me its not unit but some use units! Please verify the following Quantity Dimension Length L Mass M Time T Temperature Θ Amount of...

Some books say when heat flows into a monatomic gas at constant volume, all of the added energy goes into an increase in random translational molecular kinetic energy. But when the temperature is increased by the same amount in a diatomic or polyatomic gas, additional heat is needed to supply...

I'm trying to figure out what the physical meaning of divergence is for a vector field. My textbook offered the following example: if v = <u, v, w> represents the velocity field of a fluid flow, then div(v) evaluated at P = (x, y, z) represents the net rate of the change of mass of the fluid...

why isn't solution state a true physical state but a pseudo state?

I read somewhere (article, messageboard, i can't find it anymore) that motherboard bus speeds are limited because if the frequency gets too high then the signal will disappear. I guess I understood it to mean that the bus wire will become like and antenna if the frequency is too high. They...

Homework Statement The dissociation constant Ka for the acid-base reaction HA-->(H+)+(A-) is given by Ka = products / reactants; but instead of listing Ka, people generally list pKa = -logKa (where log indicates the 10-base logarithm). Similarly, instead of using [H+], people generally use pH...

So, I know that there are already three absolutely mandatory physical constants, like the gravitational constant, the Planck constant, and the speed of light. But what if you only changed the value of one constant? For example, if you changed the value of the gravitational constant to 4.4663 x...

Hi! Sorry if this is the wrong section to post this: I am doing a laboration on physical pendulums and I have a bit of trouble making sense of it all and I am in need of some guidance. When I do the analysis I get the standard mathematical pendulum. [T]=[m]^a*[l]^b*[g]^c, where a = 0, b = -c...

Hello all I know that the step response of a second order underdamped system is : y(t) = 1 – (e^(-ζωn*t) / sin(θ))*sin(ωd*t + θ) Where sin(θ)= sqrt(1-ζ^2) , ωd = sqrt(ωn^2 – ωn^2 * ζ^2 ) my question is: I can see on the simulation ωd and I can calculate it , but I want also to see the...

First, I'd like to thank everyone that has helped me thus far in deriving the general relativistic tensors for the Morris-Thorne wormhole metric in an orthonormal basis. I have finally done it and grasped that concept. Now that I have done that, my new stress energy momentum tensor for this...

Does anyone here know much about these topics? I understand they surround the absence of normally distrubted returns, excessive kurtosis. Fat tails somehow disprove the EMH? Can anyone explain this argument? I've been advised that there are links to turbulence in fluid dynamics, joined by the...

Homework Statement For the reaction: 2SO3(g) →2SO2(g)+O2(g) when 2.00 mol of SO3 is added to a flask at 10.0 L and 350 K at fixed volume, at equilibrium the ratio of SO2:SO3 is 0.663. What is the values of the equilibrium constant? What is ΔG° at this temperature? Homework Equations...

In this paper, the Orbital Polarization (OP) is defined as: $$OP=\frac{n_{x^2-y^2}-n_{z^2}}{n_{x^2-y^2}+n_{z^2}}$$ where $$n_i$$ is the occupancy of that given orbital. I would like to understand the physical meaning of this. Also, is there a difference between OP and Orbital Hybridization?

We use ms-1 for unit of speed. But what is the physical unit for teleporting a mass to a distance L? Is it also [L]/[time]? But it seems it does not take time for teleport. I am seeking help. Thanks very much.

We use ms-1 for unit of speed. But what is the physical unit for teleporting a mass to a distance L? Is it also [L]/[time]? But it seems it does not take time for teleport. Seeking help. Thanks p.s: my reference http://www.nature.com/nature/journal/v488/n7410/full/nature11332.html

I understand the derivation of the equation Force=power/velocity, but I'm not sure I quite understand the physical interpretation of this. If you had a constant force acting on a particle in a vacuum, then it would gain velocity and as it did so the power would have to go down for the force to...

Hi I'm new to this site, so I'm not sure where to post this question but chemistry seemed fitting. I'm current taking 2 thermo classes, engineering and chemistry, and I'm having trouble with the concept of enthalpy. This is what I believe I understand. I Hope the following is all correct if...

Homework Statement Given the functions Q(v,w) and R(v,w) [/B] K = v(dQ/dv)r and L = v(dQ/dv)w Show that (1/v)K = (1/v)L + (dQ/dw)v (dW/dv)r I have the problem attached if for clarity of the information. Homework Equations I assume everything is given in the problem. The Attempt at...

From a mathematical point of view there can and is many different infinities that exist. I'm curious what happens when we try to use a physical infinity in cosmology. I'm not going to lie I don't even think my brain is capable of comprehending this but can two physical infinities exist...

Homework Statement A physical pendulum, consisting of a uniform rod (of mass M and length L) with an attached blob, can oscillate about an axis that goes through one end of the rod. The mass of the blob is also M. The distance of the blob to the rotation axis is x. The aim is to derive a...

Hi if i have a function that relates time and distance travelled, is this correctly understood: (please tell me what is correct and what is wrong - it would help me understand) The function is f(t)=16(t^2) 1. f(4) = 256 This tells me that at the END of 4 seconds (or is it at the...

There is a famous example that electron couldn't absorb the whole incoming photon without emitting another one. Instead of the normal way, I try to prove it simply by argument ( which might be wrong ). There are four constraints in the process, one from energy conservation, three from momentum...

Here : http://en.wikipedia.org/wiki/Penrose_interpretation One reads: I wouldn't be a liar to say that I understood almost nothing about this...what's the formulation behind it? First of all, how can the wf be a physical wave? it corresponds to what? Also I find obscure the use of...

What is the relationship between the differentiable manifold that is space-time and the physical space around us? How does one relate the three seemingly Cartesian coordinates around us, those which we can measure out with a ruler, to the coordinates of the Lorentzian manifold? If i say, measure...

Sometimes people ask a question and when I answer them in terms of equations, they say they want the physical reason, the real reason.. 1- Do you think there is a distinction between physical and mathematical reasons? 2- If your answer to the last question was yes, explain the distinction! if...

Hi there. I'm reading Gurtin's 'the mechanics and thermodynamics of continua', and working some exercises of his book. In the section 21: 'The first law: balance of energy', after the derivation of the balance equation, he uses an identity to rewrite the balance of energy. The balance of energy...

Currently I'm reading Magnetostatics. While reading Divergence of B, I fell into a confusion that what divergence really means w.r.t. a coordinate system. Supposed there is a current distribution J at r' w.r.t. some primed coordinate system. And B is defined at position r w.r.t. unprimed...

Time as a Derived Physical Quantity Consider a physical system whose state changes and let us call it a Dynamical System. Let a closed Dynamical System, S, whose state be described by ψ-- A mathematical entity we use to describe S (or the state of S). ψ can take on the following...

Modes is usually encountered in physics when we study wave propagation of any sort. Every frequency has n number of modes depending on boundary conditions - I know that much but, find it difficult to relate to so many concepts in which modes get mentioned and they baffle me at times. I want to...

Just as we have orthogonal vectors/vector spaces/etc., we can have orthogonal functions/function spaces/etc. I'm trying to apply these concepts to physical processes. Here's a general idea of what I'm doing: Suppose you have a physical quantity you are trying to measure, ##F##, and it depends...

One theory I've heard and which I find interesting is that entanglement between any pair of two-state systems could be explained deterministically by a spacelike connection which can only communicate something relative, like a phase difference, and which is essentially holding the ends...

Here is a fun talk by Fay Dowker on a path integral approach to the Greenberger-Horne-Zeilinger (GHZ) correlations. It's a physical instantiation of N. David Mermin's "no instruction sets" for GHZ in his Am. J. Phys. paper "Quantum mysteries revisited," v58, Aug 1990, 731-734. The talk...

After studying the methods of Lagrange and Hamilton for a bit I still find myself uneasy about the action. I don't even know how to define it other than the integral of the Lagrangian with respect to time: $$I=\int_{t_1}^{t_2}\mathrm{d}t\, L(q,\dot{q},t)$$ Does the action have any...

What are the physical interpretations of ##\mu_0## and ##\varepsilon_0##, the magnetic permeability and electric permittivity of vacuum? Can these be directly measured? How?

So as the title says, what are the physical reasons behind requiring the connection between tangent vector spaces to be metric-compatible? My guess is that this is desired from wanting different points in space-time to be "equivalent", in the sense that if any two vectors at a point are the...

I have been looking into broadening mechanisms and I'm stuck at trying to provide a physical explanation for power broadening. I get how the math shows that at high intenseties the decay rate goes through the roof due to saturation, but how does this increased decay rate manifest in a spread of...

Homework Statement If \mathbf{r}, \mathbf{v},\mathbf{a} denote the position, velocity, and acceleration of a particle, prove that \frac{d}{dt} [\mathbf{a} \cdot (\mathbf{v} \times \mathbf{r})] = \dot{ \mathbf{a}} \cdot (\mathbf{v} \times \mathbf{r})Homework Equations The Attempt at a Solution...

Well generally it has come to my attention that a lot of people answer to some questions with the comment: "well, that's like saying that if the laws of physics are like X" -X the false statement- "then Y is true" -Y false conclusion. Well that's not really enlightening I think. The main...

I have a sprained ankle. On my first visit to the therapist, he stuck a bandage on my ankle, such that it went 270deg around. Issues: 1. No mention of how I am supposed to shower. Do I take care to leave the bandage or do I let it peel off? I take a shower everyday, and there is no way the...

Dear all, I am going to attend masters program in micro and nano technology. I would like to know what concepts of maths and physics I should be clear at and some good textbooks for the same. My study module includes nanoscience, nanomaterials and nano electronic design.

By a frame I mean four orthogonal vectors for which one is timelike and the others are spacelike. In a bypassing some time ago I read something about the basis vectors in a frame representing sticks and and a clock. However, the author also noted that this interpretation was problematic. I...

Difference between physical property and physical quantity?? Hi I'm confused after reading the definitions of physical Quantity and physical property: Definition from wikipedia: physical quantity= is a physical property of a phenomenon, body or substance that can be quantified by...

Hi, Consider the various kinds of objects we have in our universe, from the smallest to the largest - sub-atomic particles, atoms, molecules, single-celled organism, multi-celled organisms, cities, countries, planets, stars, solar systems, galaxies, collection of galaxies, universe. Since...

If Newton is unit for measure force, meter is unit for measure length and radian is unit for measure angle, so, bel is unit for measure which physical(/mathematical) quantity?

I am able calculate the solution for the TISE relating to the interval to the right of a step potential; however, I am unclear as to what this solutions represents physically for this scattering problem. So, starting with (-ħ2/2m)d2/dx2Ψ2(x) + V(x)Ψ(x)2 = EΨ(x)2 where V(x)Ψ(x)2 =...

Using differential forms and their picture interpretations, I wonder if it's possible to give a nice geometric & physical motivation for the form of the Electromagnetic Lagrangian density? The Lagrangian for the electromagnetic field without current sources in terms of differential forms is F...

HCl(l) + H2O → H+(aq) + Cl-(aq) or is it HCl(g)+ H2O → H+(aq) + Cl-(aq) If HCL is liquid is it dil. or conc. ??

Hi everyone, I've been reading transformers and this question came in my mind. I'm unable to find a satisfactory answer. Why does the current increase in a step down transformer? I am aware of V1I1 should be equal to V2I2, but I was looking for a physical reason for the current to...

Hi all, I am trying to calculate the damping coefficient of a linear viscous dashpot/damper given the dimensions of the piston, and the dynamic viscosity of the damping fluid. I have found this calculator, but does anyone know the equation that it uses...

Is there a difference between cosmology and physical cosmology? The two have separate wikipedia pages which seem to say essentially the same thing. Also, cosmology is obviously a branch of physics, so is "physical" redundant?