# All Questions

22 views

### Two conductor's in a magnetic field, canceling each other's EMF?

If two conductor's are in a $\Delta$B, oriented the same in the field, and they induce equal $\epsilon$, can their wiring be oriented in a way that they can cancel each other's induced $\epsilon$? So ...
45 views

### Caustic airy equation and divergent series [closed]

How is the behaviour or creation or mathematical explanation of a caustic related to the divergent power asymptotic series in the limit $x \to \infty$?
546 views

### Energy Dispersion in Young's Double Slit Experiment

In Young's double slit experiment, when you see the diffraction pattern, why does the intensity of the light fade out as you move from the central maximum? I think it has something to do with the ...
82 views

### Frequency dependance of sound wave reflection

Why are high frequencies reflected more than low frequencies off an 'acoustically hard' surface such as concrete? I basically understand that the amount of reflection is determined by the impedance ...
55 views

### Mixed two-point vertex in QFT

I am considering a theory with two fields, say $\phi$ and $\psi$. The Lagrangian contains quadratic terms, i.e., propagators for both fields and a quartic interaction term for one of the fields. ...
290 views

### Normalization of a wavefunction that's superposition of two unknown energy eigenfunctions

Question:$$\psi(x)=A(3u_1(x)+4u_2(x))$$where $u_1(x)$ and $u_2(x)$ are energy eigenfunctions. How to normalize function $\psi(x)$? My intuitive solution: I got ...
99 views

### Scalar Yukawa Theory in non-relativistic limit

I'm new to QFT, and am enrolled in a class at my school. I feel as though the teacher didn't give us the tools to tackle this problem yet. It's only the second week and we've gone through at most ...
69 views

### For thermal mass flow measurement technologies is it necessary to measure gas pressure to determine volumetric flow rate?

Mass flow readings from thermal mass flow measurement technologies often provide output readings in volumetric units (e.g. standard liters per minute). Mathematically I can derive the volumetric flow ...
279 views

148 views

112 views

### Thermodynamics: Caclulate final temperature with hot metal in gas [closed]

I've been working on this problem for a couple of hours now, and I think that I simply don't understand the basic principles that tie into the problem: (note that I attempted this problem and it was ...
63 views

### Diffusion of particles

If $n(\vec{r},t)$ is the number of particles per unit volume and $V$ the volume, then $N = nV$is the number of particles in volume $V$ For a small volume, it should be $dN = d(nV) = Vdn + ndV$ But ...
78 views

### Finding charge density from from differential form of gauss law

I didnt get why he didvided and multiplied by r^2.This question is from d j griffith .
180 views

### Can the diffraction/interference pattern behind the slit (double slit) be calculated with Feynman path integrals (QED)?

I often see Feynman path integrals explained by a graphic which shows the slit and then the electron goes all possible ways behind the slit. Ok that is nice to understand the Feynman path integral, ...
904 views

### Flow Resistance and Pressures in Split Pipes

I am doing some simple flow experiments and my instruments are giving me strange results - I think they are broken, I need a sanity check for my understanding of the flow in my system to confirm it. ...
30 views

### Distribution of refractive index of water when applied pressure wave

I was wondering when applying pressure wave, ultrasonic sound waves, under water, how I would be able to measure the distribution of the refractive index.
63 views

### Use a Delayed Choice Quantum Eraser to communicate Faster Than Light [duplicate]

In the experiment setup picture of the Delayed choice quantum eraser, photons reach D0 and shows a pattern, before its quantum entangled counterparts reach one of D1, D2, D3, or D4. The pattern ...
68 views

### Reason behind the train remaining intact to the Train track

I was wondering why trains moving at such hard speeds remain intact to the railway track even while turning. Is it because of friction ?
173 views

### Two masses on frictionless table with one string connecting both masses on ground and the other string [closed]

From Morin's Introduction to Classical Mechanics page 342: A solid cylinder of mass $m$ and radius $r$ lies flat on frictionless horizontal table, with a massless string running halfway around ...
29 views

### Can anyone give me a simple proof for the sign change of electronic wavefunction when taken around a loop containing a conical intersection?

How and why does the sign of the electronic wavefunction changes when it is taken around a contour? For example, suppose the initial wavefunction is $f(s;S_0)$ at nuclear configuration $S_0$ and now ...
193 views

### How to show circular orbit as a precessing ellipse

A uniform distribution of dust in the solar system adds to the gravitational attraction of the sun on the planet an additional force linear in $r$ where m is the mass of the planet, k is a constant ...
44 views

### About category theory and physics [duplicate]

Could the ideas of category theory be applied to Physics, maybe simplifying how algebraic topology and sheaf theory and other hard-to-explain subjects are used in physics?
32 views

### Did the Cretaceous-Paleogene extinction event cause miniature tidal waves?

This could be considered on-topic for Earth Science, but I'm putting it here because I'm interested primarily in the dynamics of the impact. 65 million years ago, a large body crashed down onto ...
13 views

### Split property for type III algebras entails practical separability

I am reading Halvorson's thesis (http://philsci-archive.pitt.edu/346/1/main-new.pdf), however I don't understand a proof at p.50 where he tries to explain why the split property allows a local agent ...
61 views

### Divergence in interaction between induced dipoles

Suppose I have two polarizable point-particles 1 and 2 arranged on the z-axis and separated by $r$. Each particle has a dipole moment $\mathbf{p}_i=\alpha \mathbf{E}_i$. If we apply an external field ...
33 views

### How does change of pressure affect molecular rovibrational bands position and width?

Lets say I have $CO_2$ gas chamber with pressure $P_0$. How do rotation-vibrational transition bands alter when I change pressure P? Do they shift or not and why?
33 views

### Global Circulation Model of tidally locked planets for PC?

Is there some free simple Global Circulation Model that can handle tidally locked planets and can be easily compiled and used on a PC computer? It does not have to be very precise, I am interested ...
36 views

### Wave-like description of Compton scattering and photoelectric effect

I have found in the wikipedia page for QFT the following statement: ... Although the photoelectric effect and Compton scattering strongly suggest the existence of the photon, it is now understood ...
120 views

### Numerical error with simulation of electric charge in homogeneous magnetic field [closed]

So, I am trying to make an 2D animation of electric charge in homogeneous magnetic field which is perpendicular to charge's velocity. I've got the "circular" motion but the problem is that the speed ...
45 views

### Is every imaginable quasi-static locus (with non-decreasing entropy) physically realisable?

If I have an isolated composite system which is dependent on several extensive properties (say $U_i, V_i$ and $N_i$ for each subsystem $i$) then a quasi-static locus is just a continuous curve through ...
69 views

### Use mirror to see every angle around me

An applied physics question: How can I setup a mirror all around an arm wrestling table so I can see all angles of what I'm doing? The arm wresting table looks like this With the wrestlers on ...
26 views

### Will the background radiation get “dimmer”? If so when will it be “turned off” [duplicate]

This video http://youtu.be/_mZQ-5-KYHw talks about the background radiation which we can observe today. It's from the beginning of the universe and has traveled so long that the expansion of the ...
32 views

### If i had a aero-nautical object [closed]

If i had a aero-nautical object with a span of 10 feet and a weight of 40 pounds with a strong gale blowing do you think i could make it off a cliff with out plummeting to total utter death?