Recent content by dam

It is generally said that thermal expansion is a process determinated by the anharmonic terms in the potential of a crystalline solid. However, in the Course of Theoretical Physics by Landau Lifshitz, Statistical Physics part 1, paragraph 67, a form for the coefficient of thermal expansion is...

After a month or so I solved it, but not by expliciting the y', I only managed to do it through some variable change.

Yeah the problem is that the resulting two equations not solvable by separation of variables or any other way that I know (I'm not very good at differential equations so it may be that instead they are very easy to solve, I don't know).

Yeah I'm sorry if I wrote it so terribly, I'm not English so I did My best. As for the form of the equation, I didn't change it, that was the way it was written, so it should supposedly help to solve it. Actually written in that form it is quite clear that the equation is solved by two families...

Hi, can anybody help me with this differential equation? (px-y)(py-x)=a^2*p, where p=y'. I tried to solve it by expliciting the two solutions for y as functions of p and x and then derive, in order to obtain two first order differential equations in p but these are impossible to solve. I also...

Hi, I've only read this post now but I have exactly the same problem! Later in chapter 33 he says that it is possible to show by knowing the field for a layer of charge that the shift should be 180° but it seems just the opposite. Have you solved this problem?

Actually I know how it is usually taught (Feynman himself uses the more common approach in the second volume), so it's not a problem of understanding the subject, it's just that I am curious to know how things that everybody think can only be shown by means of Maxwell's equations have actually...

In Feynman Lectures on Physics (you can find it online), chapter 33 of volume 1, the author derives Fresnel's formulas for the coefficient of reflection in an unusual way by making considerations about the different possible polarization of light. In this way he derives the squares of the...