Comment by jacquesm
1 day ago
I can lift a 200 pound piece of glass with a tiny vacuum sucker. It's the atmosphere keeping that thing up there, and the 2" of ground clearance is what you see around the edge, we don't actually know what the distance is where the evacuation happens. For all you know it as a 3' x 7' plate underneath it that floats just above the surface.
I've done a lot of vacuum picking and it is surprising how large an object you can pick up with a tiny bit of surface.
Could you pick up, say, a manhole cover?
Mythbusters lifted a 2 ton car using a consumer grade vacuum cleaner. the math is this: the air pressure over 1 sq meter is about 10 tonnes, so if make a box with that area and reduce the pressure by 0.25 atm, you get a force of equivalent to 2.5 tonnes, enough to lift the car.
https://www.youtube.com/live/GbqKwPktCdo?xstg=CAMSBhUDze3xHw...
I'm surprised a vacuum company didn't beat them to it. That would have made a pretty great marketing campaign ("the vac with enough suction to lift a car").
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Atmospheric pressure is around 14psi, at a rough guess a manhole cover is around 200lbs so you'd need just a little over 14sq in to make that work.
F1 has taught me: yes, and it will destroy your car.
Sure, why not?
The seal won't be perfect so you'll be running the pump more or less continuously. Apropos manhole covers: I wonder what would happen if this car would drive over one. Or was that your point?
This is why they temporarily spot weld manhole covers before street races.
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There is a racing car at a car museum, it was either BMW or Mercedes, which was mounted to the ceiling because it had a suction fan that would, in theory, let it do that.
Are you sure it wasn’t the Porsche 956?
Oh it might have been! I visited them all, but long ago.
This is not how it works. It’s not sucking against the road, it’s pushing against it with thrusters at the top of the car.
No it’s not. It’s vacuum underneath.
I think we are saying the same thing, and both of us agree that it's not "suckers" like the original commenter said.
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