#saw an analogy that was “if a hula hoop passes over me I don't speed up” both ends of the hula hoop are moving at the same speed come on no | Explore Tumblr posts and blogs

bugfeelings · 1 year ago

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there's this thing going around twitter at the moment and it makes me so mad I'm legitimately going to have to start blocking people for their incorrect opinions on this thing that objectively has two separate correct answers and I'm yet to see anyone pick either of them

Discourse below the cut

YES this is my sheldon big bang theory moment I'm about to be VERY obnoxious BUT I keep seeing people saying "A" and it's B!! IT'S B!!!

Listen. There's no such thing as inherent momentum. Your motion relative to the portal is what matters. This is why when you jump into a portal that's on an angle you get shot out on an angle even if you went in 'straight' from your perspective. From the portal's perspective, you're moving towards it at tram speed, so you should exit the second portal at tram speed.

Like ok, you'd expect there to be wind coming through that portal, right? because if you're standing on the front of a moving tram you'd feel wind. But the air that becomes wind when you're on a moving tram is motionless relative to the ground! If all the air that went through that portal maintained its momentum relative to the ground as it came through the air would be completely motionless (well, it would expand in every direction to fit the new air in), and that's (I hope) obviously wrong.

Mythbusters did something like this, actually. And if you wanted A to work when you went back through the portal (as in you're deposited unmoving relative to your original frame of reference rather than the portal's frame of reference), you'd need to instantly accelerate to the speed of the tram as you went through the portal. That's a lot of Gs!

The SECOND correct answer is portals aren't real & even in the game they disappear if the surface they're on moves (I would assume to avoid devs having to program this exact scenario because in a video game world there is such a thing as absolute momentum and having to bypass that wouldn't be impossible but it would be really annoying & probably frustrating & counterintuitive to players)

#chats #like how are you moving through the portal at ALL if you're tied to the train tracks and momentum isn't relative to the portal #if you don't have to step through the portal then you don't need to have 'inherent momentum' (not real) to go through a portal #you only need momentum relative to the portal #why would the portal only impart SOME of that momentum (enough to plop you out)? How would it know what proportion to give you?#saw an analogy that was “if a hula hoop passes over me I don't speed up” both ends of the hula hoop are moving at the same speed come on no #actually though it's an interesting point how would it feel to not be moving and then to be moving quite quickly #but there's no acceleration in one frame of reference but an instant acceleration in another #THIS WOULD BE AN INTERESTING DISCUSSION BUT IT'S NOT THE ONE PEOPLE ARE HAVING #THE ONE PEOPLE ARE HAVING IS 'it's option A because of absolute momentum' (ONCE AGAIN NOT A REAL THING)

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