Recent content by Tom83B

If you can program there are quite a lot of things you can do. If you can't there is still enough time to learn until summer. But you shouldn't disregard experiments just like this. I used to be the same, but understanding how something is measured is very important.

I'm an udergrad, 2nd year physics. I recently got interested in solar physics - one reason being, that I was offered to cooperate on a project, where I'll be doing some sunspot simulations. I really like mathematics and I kinda like the mathematical modelling curriculum. However the...

Oh I see now! It can have no non-trivial symmetries and permutation (1 2) is already a non-trivial symmetry. Sorry to bother

Why isn't this graph: 1-2 3 asymetric? I think there exists only one automorphism: 2-1 3 but I'm also supposed to prove that ther are no asymetric graphs with 1<|V(G)|<=5 so it can't be asymmetric

Hi, I'm fresh out of high school, studying physics on Charles University in Prague. It's not a bad school, but my ambitions are bigger. I'd like to continue with my master's or phd degree somewhere like ETH Zurich (I've read about the excellence scholarship - covers tution and living costs) or...

Hi, I'm trying to simulate different expansions and processes in gas and I have 3 questions: If the average distance, that a molecule goes without hitting another one is l (by the way, could you please tell me what this distance is called in english?) and x is the distance it's already passed...

Thank you very much :-)

This is in my book: exp[2\pi i(hx+ky+lz)][1+exp(\pi i(h+k+l))]=2exp[2\pi i(hx+ky+lz)]\cos^2[\frac{\pi}{2}(h+k+l)] And in order for the cosine not to be zero, h+k+l must be even when we want to see the reflection. But I think that the result should be exp[2\pi...

There's this text that is supposed to help us with some problems in one competition (I could send the link, but it's pdf in czech...) and there's written, that y_{,z}=-i. It's about complex numbers so the z is probably a complex number, but I can't see why the derivative should be -i...

It's just a guess, I don't know if there's any research needed, but what about plasma TVs?

If I wanted to become a theoretical physicist, would it be useful to learn russian? It's a fairly easy language for me, as my native language is czech which is very similar. I somehow have a feeling that they have some good research centers or accelerators. It's not that it's my dream to work...

Sorry it's to hard to read that. Use TEX and explain what is what... But as far as I can gather from your posts - you're right that \frac{Ds}{V_s}=T-t_f. For free fall applies h=\frac{1}{2}gt^2, in this case Ds=\frac{1}{2}g{t_f}^2. Now you just need to solve these two equations. Sorry I...

You have a given time - T. The time of the melon falling is t_1 and the sound travels T-t_1. Now you have two variables (time and distance) and two equations. Solve these and you get the result.

I know it's quite far - but this is a kind of bachelor degree in cryptography... http://translate.google.com/translate?js=n&prev=_t&hl=en&ie=UTF-8&layout=2&eotf=1&sl=cs&tl=en&u=http://www.mff.cuni.cz/toUTF8/studium/bcmgr/ok/m1a33.htm&act=url

I think I would never have the guts to do it :-)