Physics Challenges: Similar to Math Ones?

[wrobel]

What about Physics Challenges similar to Math Ones? Sorry if it is inappropriate place for this topic

 

[fresh_42]

What about Physics Challenges similar to Math Ones? Sorry if it is inappropriate place for this topic

Did you prepare an answer to the inevitable question?

I have thought about physical questions within the math challenge and ran into the following problems:

• classical mechanics etc.: all trivial calculations, get the formula and plug in the values
• vector calculus in all variations: most examples are spheres, some paraboloids, and at most a Möbius strip
• an interesting question about Noether remained untouched for long
• the remaining rest are some index acrobatics and functional analysis

I couldn't found good questions, except those which were asking to detect the physical laws of an experiment. However, an answer to that kind of question would be a copy and paste from the according Wikipedia page, or alternatively lead to endless discussions of why's and why not's.

 

[wrobel]

Just as an example. There is a perfectly rough horizontal table. This table is pretty wide (actually it is a plane) and it rotates about some vertical axis. Angular velocity is a given constant:##\Omega\ne 0##. Somebody throws a homogeneous ball on the table. The ball has a mass ##m## and a radius ##r##. The ball begins to roll on the table without slipping.1) Prove that the center of the ball describes a circle relative to the lab frame;

2) Having initial conditions, find the radius of this circle and the distance between the center of the circle and table's rotation axis

 

[Greg Bernhardt]

We would LOVE to have someone volunteer to create monthly physics challenge threads. @fresh_42 goes above and beyond, but it would be great to have a thread with say 3 problems. Anyone?

 

[fresh_42]

There is a reward for those who are interested: Pose questions you're not familiar with at first glance.

Thus you can learn a lot on the way. E.g. I'm currently preparing questions for upcoming threads. I had an easy question, but on the way to find a proof I walked through several theorems and their proofs in order to find a solution. Ok, I discarded some attempts, and at the end I found an argument without all those theorems. However, I learned some interesting stuff and one of the proofs can be used for another question.

 

[Infrared]

@wrobel Since you already have an idea for what sort of problems would be good, perhaps you'd like to start such a thread? I'd guess that it would receive at least as much traffic as the math challenge threads, which are already pretty popular.

 

[PeroK]

We would LOVE to have someone volunteer to create monthly physics challenge threads. @fresh_42 goes above and beyond, but it would be great to have a thread with say 3 problems. Anyone?

I've got a few problems that might be interesting. I could do one a month for a year or so.

 

[wrobel]

@wrobel Since you already have an idea for what sort of problems would be good, perhaps you'd like to start such a thread? I'd guess that it would receive at least as much traffic as the math challenge threads, which are already pretty popular.

I am a mathematician and in physics I am expert in classical mechanics only. I can propose several problems in classical mechanics. One of them is above.
As for opening such threads it is up to Administrators decisions I guess

 

[Greg Bernhardt]

Can you send them to @fresh_42 and then maybe he can create the thread with two moderating it?

 

[PeroK]

Okay, I'll do that later today. Working on an Insight today ...