You know like the kind that go on a window or bathroom mirror or on the wall or in the shower. They need the atmosphere pushing down on them to work, right?
That’s a really good question. I have a (crappy) vacuum chamber, I’ll give it a go. I suspect they won’t!
I wonder if you would have to stick it while in vacuum for the condition to really be replicated.
It’s a good line of thinking for trying to be scientific (how do we replicate conditions better, and where might we be introducing errors that would make the experiment “bad”), so you didn’t deserve a down vote.
That being said, it won’t change the outcome too much. In a vacuum, it’s just pushing a bit of rubber against something, there’s no possibility for suction. It’ll just fall off.
If it starts outside a vacuum, the force of air pushing on the outside will keep the rubber from pushing away from the surface at first, but as the air pressure drops, the little bit of air under the cup will give it the tiniest oomph of extra push as it falls off in a way visually indistinguishable from the vacuum scenario.That’s my prediction as well, but if the experiment is cheap to run, why not do so, and see of you learn something?
No reason at all not to. :)
Should deflate and fall off while the air is pumped out.
Suction cups aren’t held by the vacuum they created but by the outside air pressing them down.
Yes. They won’t work because they operate on a difference in air pressure providing a force. No air? No force. Same reason an airplane wing won’t provide lift in the upper atmosphere.
But, compare to a rocket engine that does NOT need an atmosphere to push against.
Phrases I did not expect to think this early in the morning: "what’s the rocket engine of suction cups?”
Selotape? It’d have to be something that sticks on it’s own
Gecko skin!
Magnets
[Confused Juggalo Noises]
Velcro, or maybe Van Der Waals force, or maybe whatever the hell makes gauge blocks stick to each other.
If it’s metal, just rub a bit of it against another piece of metal and it will cold weld/fuse to it.
This only works on “virgin” metal iirc - if it’s been exposed to Earth’s atmosphere, it won’t work. If you shave off some from the surface I believe it works again.
Like I said- “rub it”. The oxidized layer on metal is very, very, thin. It doesn’t take much at all to get rid of it.
I didn’t realize that the layer was thin enough to rub away with minimal friction. I’d learned about this years ago so I could be misremembering things, but the source I read made it out as if it wasn’t a major concern with space exploration because it took substantial effort to cold weld things that had been exposed to air.
Actually, it’s believed that some of the failures in early satellites was due to cold welding.
I like the gauge block notion. A (quick) search says that it’s a combination of surface tension from the oils they’re coated in, suction (gone for us), and the super flat surfaces slightly exchanging electrons and bonding in close proximity.
I’m a fan of the surface tension angle as the “rocket of suction cups”, since it’s got that “non-binding force” element, where welding or glue feels different, and Velcro feels like a tangle.
It’s “pull-y” where suction is “push-y”.Now the question is would surface tension grab something in a vacuum the way it does outside of one. I know you’d have water sublimate off, so it’s questionable to me.
Just a technicality, but the Kashmir effect would still provide some adhesive force. It would be greatly reduced vs a suction cup in an atmosphere, but it wouldn’t be 0 force.
Though in microgravity, it might be enough to stick something to a surface, as long as it’s not getting bumped or jostled. And don’t expect it to stay in place if you need to do a maneuvering burn.
Yes the Casimir Effect.
Any good answer to a high school science question begs for a graduate level rebuttal.
Ah thanks for the spelling, swipe typing had Kashmir already so I thought that was right. Corrected above.
And yeah, even in high school I was lucky to have a physics teacher that liked delving deeper into the topics than what’s normally done at that level because my mind seems to naturally seek out those edge cases where rules as given break down. Still hoping we find one of those cases for the laws of thermodynamics lol.
Right. So just strap a Saturn V to my space suction cup and I’m golden?
The math checks out
So you’re telling me a space octopus would be powerless ?
They can still wrap their noodley appendage around you.
Hot.
Yeah, but they’re pretty smart. It would adapt.
I believe they call those “Elder Gods” or “Great Old Ones.” They are far from powerless.
Other than the fact that it’s an octopus that managed to survive and thrive in outer space, yes.
They survived space, but didn’t really thrive until arriving on Earth.
Don’t they also have little hooks in their cups though?
If by “in space” you mean in zero-G inside a spacecraft, yes. If you mean in a vacuum, no.
ActionLab tested it on YouTube:
Correct, they require air pressure to work.
Could work inside a spaceship/station.
