Recent content by 3102

Hi! I'm studying physics and currently taking the first mechanics course. After dealing with rotation and gyroscopes, now we're working on things like shear stress, and Hooke's law in tensor form etc. I've got Kleppner/Kolenkow but shear stress, Hooke's law in tensor form and tensors in...

Hello, I am working through the MIT OCW courses 8.01 and 8.012. At my university we already learned about tensors in the first mechanics course but I don't really understand them completely. Therefore I am searching for some MIT OCW course that covers tensors. I'd be glad at any help. Apart...

Hi! At university I have got a problem set with lots of inequalities. Unfortunately there are no explanations given how to do them. In Highschool we only did very easy inequalities. Therefore I am looking for a resource for inequalities. Especially for more difficult inequalities like $$ 1...

Homework Statement I have given the statements: ##a_{n}^2 \ge x## , ##a_{n+1} \le a_{n}## , ##x > 0## and ##\inf a_{n} > 0 ##. How to prove the following: ##\lim_{n \to \infty}a_{n}=\sqrt{x}##Homework Equations ##a_{n}^2 \ge x## , ##a_{n+1} \le a_{n}## , ##x > 0## and ##\inf a_{n} > 0 ##...

By this I mean the 3 formulae, one for each coordinate direction x,y,z; the expansion of the cross product. ##\tau_{z}=xF_y-yF_x## Where do these equations come from?

Wow, thanks for all your answers. But, now I've got 2 more questions: A) Was the cross product because of the long formulas in physics or was it independently developed in mathematics? B) If the cross product was developed in physics, how did they get to these long formulas for rotational motion?

Thanks for your answer. Now I have got 2 more questions: 1. How did physicists find out that the quantity "r x p" is the useful quantity? I assume that they did not try all possible combinations of quantities. 2. How did they know that they should use the cross product? I don't think that they...

okay, why is the particular quantity "r x p" so useful? And for me way more important: How to find out which quantity is important and which not?

But how do you know, that this particular quantity r x p is so useful? Is there any passage in the book that shoes you that this quantity is so much more useful than any other quantity?

BUT: An gyroscope behaves in a way that is not influenced by our definitions. If I took another definition for angular momentum (e.g.: the one mentioned above) then I would compute a totally wrong "forecast" about the gyroscopes motion. So, at least for my part, it does not seem like an...

I am reading "An Introduction to Mechanics" by Kleppner and Kolenkow (2014). On page 241 is the definition of the angular momentum: "Here is the formal definition of the angular momentum $$\vec{L}$$ of a particle that has momentum $$\vec{p}$$ and is at position $$\vec{r}$$ with respect to a...

Thanks for your responses! 1. @verty: "Then I suppose it is time to learn some E&M." Question1-Do you think that I've already learned enough mechanics? Question2-Aren't there more things to be learned than in the Feynman Lectures? For example I've been wondering about the following...

I have studied all of them. Chapters 18-21 were especially interesting - most of all the prove why you can treat torque as an "artificial vector"

Hello! I am going to start physics at university in autumn and I want to prepare for the university start. Up to now I've been reading the Feynman Lectures on Physics Vol 1. and 07.01 on OCW by the MIT. In my opinion I am ambitious and therefore I want to use the best books and learning...

Hello, I only post this here, since I can't post in the learning materials section of this page. I am going to begin studying physics in Europe in autumn. I know that I will learn a lot but I want to be really good and learn in the most efficient way. In order to achieve this I will have to...