Recent content by dykuma

I want to try to do spectroscopy of TLE's (sprites and things like that). They are quick and very faint, so using a regular narrowband filter might make them too hard to see. I was inspired by how solar telescopes use F-P's to observe fainter solar flares, and figured something similar was...

Thanks for the response, I appreciate it. Also sorry for taking so long to respond, I've been busy. Right, so the mirror I used wasn’t intended to be the final one. Mostly I was interested in seeing if it was possible at all to get fringes before I either attempted to make my own mirror or...

I am trying to build a Fabry-Perot interferometer to make some narrow band filters, and I was wondering if anyone can go into the specifics of whether there's anything special about the types of mirrors used in construction. I started by trying to see how hard it really is to make one on my...

I should have clarified, I was asking about the colors/wavelengths of light of excited gasses (N2 and O2) as a function of altitude. Lightning at lower altitudes is blue, where light from excited nitrogen is dominate, and I was considering the excitation due to lower and upper atmospheric...

Maybe a bit of an odd question (not really sure where it would belong on this site to be honest), but I was wondering if anyone can explain, or at least knows of a source that explains in a quantitative way, the physics behind aurora? Now I've seen websites like this that discuss conceptually...

Actually, I see that I made an error there. I'm not sure this makes sense though. I would expect there to be some mechanical work done (because the energy per volume is not zero), but because of the dot product (I'm dotting everything that's in the ##\hat x## direction with the current density...

To go through all of this then, does this look correct to you?

Right, so because: $$ \vec J = \rho \vec v$$ So I want: $$ P_V = \vec F \cdot \frac {\vec J} {\rho}$$ ?

So then, what did I do wrong here?

That's what I thought. However, when I tried to simplify it, I got: $$\nabla \times (\vec B \times \vec B) = \vec B(\nabla \cdot \vec B) - \vec B(\nabla \cdot \vec B) + (\nabla \cdot \vec B)\vec B - (\nabla \cdot \vec B)\vec B = 0$$ But when I actually carried out the work, I got an answer. I...

Nevermind, I figured it out. The problem was that I took the cross product incorrectly. it should have been: $$(\nabla \times \vec B) \times \vec B$$ not $$\nabla \times (\vec B \times \vec B)$$

My guess is that the force per volume is: $$ \vec F_V = \rho \alpha x \hat x + \vec J \times \beta x \hat y$$ but I'm not sure where to go after that. I'm not given a value for either the charge density or the current density, so I can't simplify the relation much. Further, I'm not sure if my...

First, I attempted to find the wavelength of the incident wave in the required terms: Next, I tried to find the wavelength inside of the material: And then lasted, I tried to find the critical angle: My issue is that 1) I don't know if what I did was correct. 2) I don't think what I did...

I think I roughly see what's happening here. > First, I will assume that AB - BA = C, without the complex number. >Matrix AB equals the transpose of BA. (AB = (BA)t) >Because AB = (BA)t, or because of the cyclic property of matrix multiplication, the diagonals of AB equals the diagonals of...

I had thought about looking through his channel, but I was not sure what to look for on there. That's exactly what I needed though. Thanks!