All Questions

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6 views

Vector potential of magnetic monopole

I am following the step on this introduction to magnetic monopole. I understand that the vector potential produced by semi-infinite solenoid is exactly the vector potential of magnetic monopole. But ...
0
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0answers
4 views

Velocity of an object orbiting on a string

First, I'm sorry if this question is dumb, incoherent or vague - I never really studied any physics and this might be out of my grasp, but I tried to apply some of the math I know and figure these ...
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0answers
5 views

Feynman story: providing two different explanations for the same phenomenon

There's a story told about Feynman in a non-scientific book (whether written by him or another, I don't recall) that I'm trying to track down. If I recall correctly: he's part of a group (perhaps ...
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0answers
6 views

Is it true that any electrostatic charge density can be represented by Dirac Delta function?Give me a general example

My college professor said that any charge density can be replaced by Dirac Delta function but how I want to know.
-1
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1answer
11 views

Is the total mechanical energy conserved in a system that's a simplifying approximation of an actual roller coaster?

Suppose you have a 2-dimensional Euclidean space where one dimension goes left and right and the other dimension goes up and down where one of the units of length is the meter. Furthermore, suppose ...
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1answer
14 views

When a proton attracts an electron in the electromagnetic field is the proton “bending” the field?

As the question states when a proton attracts an electron in the electromagnetic field is the proton "bending" the electromagnetic field like the earth bends space time ("creating" gravity)?
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0answers
8 views

What is the Spectral Form Factor?

In many papers in Random Matrix Theory [1-3] related to quantum chaos (and, in particular, to the SYK model) they analytically continuate the partition function of the system $Z(\beta)$ into $Z(\beta +...
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0answers
8 views

Unit of Mass density or density of a liquid substance

can any one tell me what is wrong with this Question. my practice test series has many question related to the mass density but all give me ANS (c) in options but according to me answer should be (a). ...
0
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1answer
11 views

Course on Nuclear/Particle physics

I would like to know if there were online resources about the following topics: Nuclear Physics Nuclear Engineering Particle Physics to go a bit deeper in my reading. I am asking for a free-to-learn ...
1
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0answers
13 views

How does approximations to assumptions lead to approximations to solutions?

I was reading Physics SE 228313. It talks about using Born-von Karman condition to model metal lattices. Is there any mathematical justification that approximations to physical condition would give ...
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1answer
35 views

Why physical / cosmological models that have been falsified weren't abandoned?

Before anything, I'd like to say that I'm a layman (non physicist) and english is not my main language; I apologize if my choice of words make me sound rude / arrogant, that is not my intent. I often ...
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0answers
13 views

2 windows - will I see the reflections?

I have a question regarding photons nature. Let's say I have a single source of light - regular bulb and the observer - in the same room. The observer looks through a glass window (normal glass ...
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0answers
9 views

How would the displacement of an object be calculated using only initial speed, coefficient of kinetic friction and the slope of the hill?

A sled takes off from the top of a hill inclined at 6.0° to the horizontal. The sled’s initial speed is 12 m/s. The coefficient of kinetic friction between the sled and the snow is 0.14. Determine how ...
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0answers
6 views

Is acceleration of particle by photon a continuous process?

There are a lot of questions, so I assigned a number to each one. Let's assume we have electron which is not moving in some inertial frame of reference. Let this electron be hit by a photon. Since ...
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0answers
8 views

Forces on a railway track with curvature and cant (inclined plane)

I'm trying to work out the forces acting on the left and the right rail if the track has curvature and cant (i.e. is an inclined plane) I've come this far as you see in the picture but I'm struggling ...
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0answers
9 views

Diameter to prevent water flow into a closed-end tube?

Imagine I drill three holes of different diameter into a large block of plastic but the holes don't go all the way through. (They form three close-ended tubes, see the image.) I then submerge the ...
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0answers
15 views

Is there a real proof that Stern-Gerlach Interferometer is behaving like it wasn't there, exactly the same spin direction at output as input?

Have you heard of, know or performed an experiment with a Stern-Gerlach Interferometer (SGI) that would prove that it is really behaving like it wasn't there. We obtained exactly the same spin ...
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3answers
19 views

How is an Isobaric process consistent with the first law of thermodynamics?

Suppose there is an isobaric process whereby the volume of a gas decreases while the pressure of the gas remains constant. Work is done on the gas to compress it. Since the change in internal energy =...
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1answer
10 views

How can I determine what degree of polarization my polarized film is?

I have a piece of linear polarized film that I had laying around, however, I have no knowledge of the degree of polarization that the film has. How can I test to see what the degree of polarization is....
1
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1answer
29 views

Meaning of “a force that derives from potential energy”

In mechanics course, when the idea of equilibrium was introduced they included the idea of a force that derives from potential energy which is the force $F$ which is related to the potential energy $...
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0answers
5 views

How does reflection and refraction of light behave for a colloidal solution of glass nanoparticles?

If I have a colloidal solution of glass nanoparticles (10-100nm diameter), how much of an effect does refraction and total internal reflection have on the transmission of the light? I know that if the ...
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0answers
26 views

Misconceptions in spontaneous symmetry breaking

Spontaneous symmetry breaking occurs when we have a potential like a mexican hat as shown in figure (right) and is unbroken for the potential shape as shown in left figure. Under the Symmetry ...
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0answers
4 views

Is there an electronic version of diffuse mismatch model for metal-metal contact thermal resistance?

Interfacial heat transport in phonon systems is routinely described by diffuse mismatch model for phonons. Has anyone come across a similar model to describe interfacial heat transport in electron ...
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1answer
15 views

Clarification on Bernoulli's Principle

I need a clarification about Bernoulli's principle. The standard way in which this principle is taught is related to a picture like this one where usually the two sections have different areas and ...
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0answers
9 views

Work of centrifugal force cartesian coordinates

Hey I have a question about an expression in the textbook of Born. There a pendulum of variable is considered. Then it is stated that for shortening a work given by \begin{equation} -ml \int \dot{\phi}...
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0answers
14 views

Understanding $\alpha$-decay energy level scheme

I want to understand the $\alpha$-decay of $242$-Curium to different excited states of $238$-Plutonium (image taken from Introduction to Nuclear Physics page 258; Author: Krane): There are two main ...
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0answers
16 views

Need help with a phase transition problem [on hold]

I need to verify these plots and also find critical indices. Please, help me.
1
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0answers
35 views

Pair production problem, how is energy not conserved here?

The problem is asking me to find the minimum photon energy that would produce an electron-positron pair when it collides with a free electron at rest. This is my attempt at trying to conserve both ...
0
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0answers
11 views

What is a good introductory text on statistical mechanics for math-student [duplicate]

Here a "math-student" is an advanced undergrad or a 2nd-3rd-year grad student but only has taken the first-year undergraduate physics classes. Ice-type models, Yang-Baxter Equations are of particular ...
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0answers
8 views

Rotational contribution towards heat capacity of an ideal gas made up of arbitrary shaped particles

Consider the particles of an ideal gas to be arbitrarily shaped, but all particles have the same shape. The Hamiltonian has a translation term and a rotational term. The translation contribution ...
0
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1answer
37 views

What are direct experimental evidences that quarks exist? [duplicate]

Now we have very established model of quarks explaining fundamental strong interaction. What are experimental proofs for existence of quarks and what is the name of physicist which made them?
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0answers
12 views

How does the Torricelli barometer create a vacuum at the top of the tube?

Hi everyone! Can someone explain to me how does the Torricelli barometer creates a vacuum at the top of the tube? And how does it work?
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0answers
12 views

Extension as independent variable?

For a force extension graph of a spring to have extension on the $x$ axis means that you change the extension of the spring, and measure the force needed to do that? Why do these exist doesn’t it ...
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0answers
43 views

What's the spin rate of an “earth ball”, as far from the sun as it is? [on hold]

I'm a EE (Electrical Engineer), and it's a while since I've had done any mechanics from my years of schooling, also a minor in mechanical engineering, but not using it "on the job." Last night, I had ...
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0answers
16 views

Would Color Confinement apply in higher dimensions?

As I understand it color confinement comes from the fact that as the distance between two color charges increases the color potential energy increases, instead of decreasing, and the energy needed to ...
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2answers
42 views

Manipulating Dirac Notation

I have trouble getting my head around manipulating Dirac notation, it's still new to me and I'm not used to it. I'm following the rotating wave approximation derivation for Rabi oscillations and light ...
0
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1answer
41 views

Who had proved that neutron is elementary particle? [on hold]

We have idea that neutron is similar to proton well established. But what were proofs initially, who did them and how? Update: I mean that when neutron was discovered, it became obvious that is is ...
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0answers
12 views

Plane capacitor with two dielectrics [on hold]

A parallel-plates capacitor has plates separated by a distance 1.0 mm. The space between the plates is completely filled with two slabs made from different dielectric materials. One slab has thickness ...
0
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2answers
23 views

Only getting positive values for induced voltage?

We have to draw a voltage over time graph for the induced voltage in a coil for 2 whole turns. $N = 10$ $B = 30mT$ $A = 100cm^2$ The coil is rotating at 20Hz We have the formula: $2πNBAfsin(2πfT)$ ...
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0answers
20 views

When is a decay mediated by the weak force

If a $\pi ^+ \to \nu_\mu+\mu^+$, here quark flavour is lost entirely. I am aware the weak force mediates decays where quark flavour is not conserved. But If I consider a $p+\bar p$ annihilating, here ...
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1answer
33 views

Science Fiction Question [on hold]

I have been reading some scifi articles where 100 kg weight is surrounded by an "antigravity" shield and accelerated to the speed of light. If the shield was suddenly removed once it was at C, what ...
0
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3answers
50 views

Does the weight of a steel ball changes when submerged in water?

Will there be a difference in the weight of just the ball under water Vs in normal atmospheric pressure conditions i.e. a weighing scale with the steel ball on it Vs in vacuum assuming earth's gravity ...
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0answers
15 views

Effect on the weight of a bird in a closed cage with a spring attached to it

I have read the question which where the difference in the weight of the bird in a closed and a open system is described. But what happens if there is closed cage but there is also a spring attached ...
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0answers
8 views

Operational amplifier characteristics [on hold]

What are the differences between the Open and Closed loop gain of an operational amplifier? Also, what is the concept of “feedback resistance” in amplifiers?
0
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1answer
19 views

Relation of Corresponding principle and law of large numbers

Is it possible that Corresponding principle can be derived from the law of large numbers? Also is the principle a postulate of Quantum Mechanics?
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0answers
9 views

Capacitance of Three Metalic Cylinders [on hold]

Three concentric, thin, long conducting cylindrical shells have radii of 12, 47, and 137 [cm]. The space between the shells is filled with air. The innermost and outermost cylinders are connected at ...
0
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1answer
40 views

What is the energy source for Earth movements?

What is the source of energy responsible for Earth movements (rotation, translation, etc.)?
0
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1answer
10 views

Effect of the magnetic field of a moving charge on the magnetic field used to accelerate the charge

Ok, so my brief understanding is that an accelerating charge will produce a magnetic field. If the charged particle, say an electron is being accelerated by a magnetic field, how does the electron’s ...
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1answer
27 views

Why should there be electrostatic equilibrium inside a conductor?

I have been trying to understand why the net electric field inside a conductor is zero regardless of the exterbal electric field. But why should equilibrium ever be attained?
0
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1answer
26 views

Significance calculation in particle physics?

I am wondering how does one calculate the significance of a "bump" in particle physics. Suppose I have a set of data: for example, in 100-200 GeV I have 700 events, in 200-300 GeV I have 600 events,...

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