this post was submitted on 18 Aug 2023
896 points (96.9% liked)

Memes

45899 readers
1490 users here now

Rules:

  1. Be civil and nice.
  2. Try not to excessively repost, as a rule of thumb, wait at least 2 months to do it if you have to.

founded 5 years ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 32 points 1 year ago* (last edited 1 year ago) (2 children)

Speedy thing goes in, speedy thing comes out

E: I was just quoting GladOS..... Not really thinking about the actual physics!

[–] [email protected] 11 points 1 year ago (2 children)

Yeah but the thing isn't moving the portal is, and the energy has to come from somewhere if the portal makes the thing go fast.

[–] [email protected] 12 points 1 year ago* (last edited 1 year ago) (2 children)

The energy would come from the trolley. The people would launch out at approximately the same speed as the trolley interacts with them and the trolley would slow down in response to how much kinetic energy was transferred to the people.

[–] [email protected] 15 points 1 year ago (1 children)

This is correct. The motion of the people is relative to the Portal. It doesn't matter if the trolley is accelerating the Portal towards them or something is accelerating them towards the Portal. Therefore they accelerate out of the other side with some retained momentum. Technically it probably resembles something in between pictures A and B.

This reminds me of the experiment about whether an airplane could take off from a treadmill.

[–] [email protected] 6 points 1 year ago (2 children)

Only if you assume the people will experience friction against the portal.

If they would accelerate to the speed of the train within the time it takes them to go through it, they'd experience very high pressure change against the due to one part of body accelerating faster than the other. This would cause the bodies to explode out the portal

[–] [email protected] 3 points 1 year ago

Interesting. It would be the same as if the trolley hit them directly.

[–] [email protected] 1 points 1 year ago

Yes, as I noted elsewhere in the thread, the part of the body exiting the portal will experience inertia as it enters into the space outside the second portal and it will be forcefully pushed by the next part of the body heading into the first portal and thus imparting momentum to the parts ahead.

If this momentum has to be taken from anywhere its from the portal itself and by extension the train.

[–] [email protected] 2 points 1 year ago

Now you're thinking with ~~portals~~ physics!

[–] [email protected] 2 points 1 year ago

This guy is thinking with portals!

[–] [email protected] 1 points 1 year ago (1 children)

No moving objects are entering.. lol

[–] [email protected] 2 points 1 year ago

Then they can't enter at all and have to be flattened by the portal, because they must have motion too exit the other portal