Recent content by Puky

I've just realized that the factor \frac{y^2-R^2}{y^2+R^2} (or that more complicated factor I found for the relationship between \omega R and v) is just equal to \cos\theta. So \omega R = v\cos\theta. This really simplifies it and it intuitively makes sense that \omega R is just equal to the...

That was actually the first thing I tried, and apparently it wasn't obvious enough haha.

That's a great solution! It's really smart, and much easier to visualize than than my solution. I had actually thought about doing the same thing before I came up with a different way, since moving the cylinder horizontally first makes it much easier to keep track of what is going on, but I...

Thank you very much for going through all that. I tried explaining my work to an instructor, he wouldn't even listen, saying the differential angles d\theta and d\phi would correspond to the same angle and it was wrong to define two separate angles there.

My mistake, I thought it was the OP who asked that question.

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Hello, this is not really a homework question, but a question on a specific problem so I thought it belonged here rather than the General Physics subforum. This is a problem that was asked in our final exam, and I have doubts about it's "correct" solution. Here's a paint art to explain the...

Innocent bump.

That's what I was trying to do in my second post, but I couldn't come to the conclusion that the two angles have to be equal. I'll try to make it clearer what I did there so you can point out what I'm missing. Say the photon is moving in the +x direction and the resultant particles move in the...

Okay, I'm able to follow your calculation now but I still don't understand why the x-components of \vec{p}_{e^+} and \vec{p}_{e^+} have to be equal. If they are, the result easily follows from there but I don't see why they have to be. If you think of the photon as a bomb which explodes into two...

Thank you very much for your explanation. The only problem is that I'm not familiar with 4-momentum yet. Can this be shown using the classical 3-momentum, or will I have to wait until I learn about 4-momentum?

Okay, let the photon's movement be in the +x direction. Then, if the resultant particles have different scattering angles with the horizontal, the one with the greater angle should have greater momentum, so that the sum of the y-components of their momenta will be 0. Some of the photon's...

Hello. Firstly, I hope this is the right sub-forum for this question. Here's a quick question that I have. After an electron-positron pair production, do the angles that the paths of the electron and the positron make with the original path of the photon have to be equal? Another way to ask...

I've got it now, thank you very much, your answers were really helpful.

Thank you very much for your answer, that is what I was thinking. I asked because I remember running into these kinds of questions a few times, in fact right now I'm looking at a textbook that says lim x->0 \sqrt{x^3-x} doesn't exist because the right-hand side limit doesn't exist, without...