Recent content by stevenytc

If X is a r.v. that follows that Gaussian distribution with mean μ and variance σ^2, how do I find the distribution function for exp(X) where exp() is the exponent function.

oh I got it! Thanks a lot

Homework Statement A diatomic molecule, when excited, can vibrate in such a way that the relative distance between the two atoms, r(t), executes periodic oscillations. If the potential energy of the molecule as a function of r is given by V (r), the time dependence of r(t) is identical to...

ok, I understand now, thanks!

It is known that for every n > 1 there is always at least one prime p such that n < p < 2n. The Bertrand's theorem's proof I read is quite involved. I've thought of another way to prove it but I think it's too simple to be correct. Can anyone please point out my mistakes? below, Fundamental...

Demystifier, Thanks for your response. But could you elaborate on exactly how this operation violates the unitary assumption? Thanks.

Isn't the subject great? Anyone that shares my feeling please reply "I LOVE PHYSICS"

Does no-cloning theorem contradict with the possibility of time travelling? If i send a photon back in time from t1 to t0, then between t0 an t1, I could have two identical photons, in other words, i can use the time machine to clone my photons. Have I missed out something?

E_potential = - int Fc dr please check the definition of potential energy

http://upload.wikimedia.org/wikipedia/commons/b/ba/Feynman_EP_Annihilation.svg this is a standard electron-positron collision. but if positrons can be interpreted as electrons going backward in time (as suggested by Feynman and Wheeler), then can this diagram be interpreted as the electron...

Okay, so seems that I've misunderstood the question... Just curious, what if I change the question so that the resistances in the question refers to equivalent resistance? How can I solve this more complicated problem? Or, is it solvable? Thanks very much, your reply is very helpful.

Thanks very much for your idea, vk6kro. But are you sure the network you draw satisfies the condition given in the question? Consider the equivalent resistance across AD ( with the 120 ohm resistor disconnected) , it isn't simply equal to 80 ohms, because there is a second branch ( consist of...

Homework Statement A network of resistors has a pair of input terminals AB connected to a dc supply and a pair of output terminals CD connected to a load resistor of 120 ohm. The resistances of the network are AC=BD =180 ohm, and AD=BC=80 ohm. Find the ratio of the current in the load...