this post was submitted on 11 Feb 2025
486 points (94.2% liked)

Asklemmy

44978 readers
1120 users here now

A loosely moderated place to ask open-ended questions

Search asklemmy πŸ”

If your post meets the following criteria, it's welcome here!

  1. Open-ended question
  2. Not offensive: at this point, we do not have the bandwidth to moderate overtly political discussions. Assume best intent and be excellent to each other.
  3. Not regarding using or support for Lemmy: context, see the list of support communities and tools for finding communities below
  4. Not ad nauseam inducing: please make sure it is a question that would be new to most members
  5. An actual topic of discussion

Looking for support?

Looking for a community?

~Icon~ ~by~ ~@Double_[email protected]~

founded 5 years ago
MODERATORS
 

It can look dumb, but I always had this question as a kid, what physical principles would prevent this?

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 0 points 3 days ago (1 children)

This is a nice example that also makes me think more questions.

  • Will the hole punching be forward or backward?
  • Assuming infinite deceleration, for an observer on the other end of the barn, will the barn be punched through, before or after the pole-pusher has stopped?
  • For the pole-pusher, will the barn be punched through, before or after it has stopped?

Gets more interesting

[–] [email protected] 2 points 2 days ago (1 children)

The punching-through should start at the point of impact, since that end of the pole and that spot on the wall pole both know about the collision at that moment, and then the information travels back through the pole. So I think the front end of the pole would start breaking through the wall immediately, while the information about the impact is still traveling back through the pole. For that reason I think the front end of the pole might end up sticking farther out of the barn than the back end, because it has more time to so it. Would be interesting math, which I've never tried to figure out.

There can't be infinite deceleration, for the same reason that the back end of the pole can't instantly know the front end has run into the wall. Deceleration travels back through the length of the pole as its atoms squish up against the atoms in front of them and slow down.

Interesting for sure!

[–] [email protected] 0 points 1 day ago

There can’t be infinite deceleration,

I realise I should have been more specific.
Considering the pusher as a point object, deceleration of the pusher be infinite. Just another simplification so that you don't have to calculate what would happen to all the speeds in between.