B Is the Longer Path Quicker in Physics?

[valenumr]

TL;DR Summary

So, I'm well out of date from my engineering education, but can this be true? I don't think so. Conservation of energy, but I'd appreciate an expert opinion.

It's just a link,

Unreal?

[Mentor note: The thread title has been edited to be a bit more specific]

 

[valenumr]

I think I already see my logical mistake. I think only the velocity has to be equal at the end. And I found this: https://en.m.wikipedia.org/wiki/Brachistochrone_curve

 

[DaveC426913]

Well, I mean it is fake. It's CGI.
But it might not be false.

I've seen the brachistochrone curve demonstrated, so I know the principle is sound.

But I don't know for sure that the configuration in your link - with its multiple, smooth peaks - is real. I've never seen a multi-peak demonstration. I am skeptical.
I would not take the word of that video.

 

[Mark44]

IMO, the image might be CGI, but the phenomenon is real. The faster ball appears to be traveling along multiple brachistochrone curves.

 

[docnet]

Heree are two examples of this phenomenon! Isn't physics weird??

 

[A.T.]

I think only the velocity has to be equal at the end.

Exactly, final speed must be equal, not average speed.

 

[SebasHerbert]

Heree are two examples of this phenomenon! Isn't physics weird??

Oh, I remember this things, at physics classes, we tried to model such an experiment, which was interesting. I still remember how our professor said: "For those who do not study physics, natural things can be magic"

 

[Devin-M]

One of my first posts on the forum had to do with this problem:

https://www.physicsforums.com/threads/brachistochrone-problem-w-initial-velocity.995659/

https://www.physicsforums.com/threads/is-it-possible-to-solve-for-t.996132/