TransWikia.com
  1. All Categories
  2. Physics

Physics : Recent Questions and Answers (Page 80)

Find answers to your questions about Physics or help others by answering their Physics questions.

Time independence of light in optical fibers

The propagation of light in optical fibers is governed by the equation $ifrac{partial A}{partial z} = frac{beta_2}{2}frac{partial^2A}{partial T^2} - gamma|A|^2A$ where $A(z,T)$ represents the amplitude of the field...

Asked on 08/31/2021

3 answer

Does the FRW metric imply spacetime scales?

The FRW metric can be written in conformal coordinates to give:$$ds^2=a^2(eta)(-deta^2+dmathbf{Sigma^2}),$$where $eta$ is the conformal time and $mathbf{Sigma}$ ranges over 3-dimensional space of uniform curvature....

Asked on 08/31/2021

2 answer

Newton's third law (action and reaction) and work done with a wheel

I'm aware of the common misunderstanding about action and reaction canceling each other; they don't because they don't act on the same object. This is about a more subtle...

Asked on 08/31/2021 by Han-Kwang Nienhuys

2 answer

How does Fermat's principle make light choose a straight path over a short path?

This is a thought experiment where I have made a "C" shaped hole inside diamond. The refractive index $(mu)$ of diamond is 2.45....

Asked on 08/31/2021

4 answer

Can you 'derive' mathematical approximations made from Taylor approximations from limiting cases in real life?

Here, the natural length of the string is $l_o$, and pulling the string up by $x$ increases its...

Asked on 08/31/2021

1 answer

Coercivity of pure iron

Coercivity of 99.8% pure iron is 1 oe but that of 99.95% pure iron is 0.05 oe.Why such difference while both have same retentivity? Edit: I mean to say if...

Asked on 08/31/2021 by sk9298

1 answer

Can we solve the general eigenfunction of $L_x$?

Consider the orbital angular momentum in QM, labeled by $L$ ($mathbf{L}=mathbf{r}timesmathbf{p}$). In spherical coordinate, the operator can be expressed as:begin{equation*}left{begin{aligned} L_x&=frac{hbar}{mathrm{i}}left(-sinphifrac{partial}{partial theta}-cosphicotthetafrac{partial}{partial phi}right)...

Asked on 08/31/2021 by Photon-gjq

2 answer

Derivation of the Electromagnetic Stress-Energy Tensor in Flat Space-time

I am working on deriving the electromagnetic stress energy tensor using the electromagnetic tensor in the $(-, +, +, +)$ sign convention. However, I have hit a snag and...

Asked on 08/31/2021

2 answer

What exactly is a basis in the context of crystalline solids?

For the purpose of this question, I'm making the assumption that atoms are fixed in space, and as such possess no vibrational degrees of freedom. A crystalline solid is a...

Asked on 08/31/2021 by W. Ryan

1 answer

Capillary Perpetual Motion

Can anyone figure out what is wrong with this perpetual motion machine? What part of it violates physics? I found it on a website a while ago, and I couldn't...

Asked on 08/31/2021 by F16Falcon

4 answer

Ask a Question

Get help from others!

© 2024 TransWikia.com. All rights reserved. Sites we Love: PCI Database, UKBizDB, Menu Kuliner, Sharing RPP