Originally Posted by

**ThePerfectHacker** I know this is getting of topic...

But that is the ugly side of physics.

I never, never, ever been able to understand those derivations in physics. For example, my professor was showing why a hanging cable is a caternary. He set up a differencial equation and shown that hyperbolic functions solve it, good that I understand. But how did he get that equation! He just divided the section into a very small piece. And said, well it is almost like a line... some more crazy statement... and wonderful we have an equation. However, if you mimick his approach say with a parabola instead of a line, because you can say that curve is almost a parabola... the same crazy manipulations... and we have an equation... which is different!! So my problem is, how do you understand these derivations? There is no way. Which is why I consider these laws discovered by luck rather then by derivation.

It seems the rule in physics is: that it is important that it works rather than how it was derived.