Newest Questions
244,124 questions
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What is the relation between the polarization $\mathbf{P}$ and the electric field $\mathbf{E}$ in piezoelectric and flexoelectric materials?
I'm currently trying to understand electromechanical coupling effects in dielectric media, especially the link between the polarization density field $\mathbf{P}$, and the electric field $\mathbf{E}$, ...
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Series and parallel resistance problem [duplicate]
Determine the equivalent resistance between terminals “M” and “N”
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Statistical mechanics and the distribution of phases of oscillation
Imagine an elliptical region of phase space $\{(q,p)\in \mathbb{R}^2:p^2/2m + kq^2/2=E\}$ of constant energy $E$ for a 1D harmonic oscillator. Since all points on the ellipse have the same energy, ...
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Explicit FLRW Killing vector fields
Could someone please tell me if there is an article or book that explicitly lists the killing vectors for the FLRW metric with generic $K$ curvature?
\begin{equation}
ds^2 = -dt^2 + a(t)^2\left( \frac{...
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Why does a mosquito net block the breeze?
When my window is fully open, I can feel the breeze from outside. But when I put on my mosquito net, the breeze gets blocked almost completely. Why does mosquito net block the breeze, even though its ...
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Derivation of gravitational redshift by Schutz
In section 5.1 of 'A First Course in General Relativity' Schutz derives the gravitational redshift relation the following way:
'Let us imagine performing an idealized experiment, first suggested by ...
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Why do speed of different colours of light vary in glass but are the same in vacuum? [duplicate]
Light is an electromagnetic wave and therefore it follows the wave equation.
$\frac{\partial^2 \psi}{\partial t^2}= v^2 \frac{\partial^2 \psi}{\partial x^2}$
Now with some maths, the wave equation can ...
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What should I do to understand Physics from scratch? [closed]
I have problems understanding physics even though I am interested in this field. Education in our country does not convey the full extent of science. I mean, I don't understand how a physics formula ...
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Good Question 135 [closed]
Вот что я понял:в зажигалке есть Пьезо элемент, который: мне не известно реформирует воздушную структуру во время прохождения электричества через воздух или вытесняет воздушную структуру на пути ...
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Noether theorem and conservation of charge
I'm trying to found an elegant, simple and very detailed proof of the conservation of charge using Noether theorem using various sources (websites, textbooks, scientific papers) in different languages....
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Classical field theory in terms of the first jet bundle
I am searching for a resource which defines Classical Lagrangian field theory in terms of the first jet bundle of some Fibre bundle $E$, meaning the Lagrangian is the jet prolongation of a bundle ...
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Huang's derivation of the grand canonical ensemble [closed]
I am reading Huang's "Statistical Mechanics", and can't understand the derivation in chapter 7.3.
7.3 GRAND CANONICAL ENSEMBLE
Although the canonical and the microcanonical ensemble give ...
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What is the maximal width of an antinode on a string? [closed]
To be precise:
Given a string fixed at both ends of length $L$, tension $T$ and linear density $μ$, if a standing wave is propagating on this string, there will be nodes of vibration and antinodes. ...
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What is the relationship between rolling resistance force and road slope? [closed]
So I am working on an electrification project of an IC engine driven vehicle and I was building a sort of motor parameter calculator in google sheets, where I can just adjust basic values like vehicle ...
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Peer Review Outside of Academia [closed]
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To deter anyone who likely will just get irritated at find out later, I am not an academic by any stretch of the imagination. Yet I've got a hypothethis that to my non academic eye, is rigorous, ...
