Wtf would make a manhole cover do this?

I'm thinking melting snow causing an underground flash flood.

So that would make air come out from the water displacing it.

Sewer gas

Pressure

I've never seen that either but let's say the manhole cover weighs 250lb.

The diameter of the manhole is approximately 32".

the area of the manhole is PI * 16^2 = 803 in^2

250 lb / 803 in^2 = .31 lb/in^2 (psi) pressure underneath for it to be neutrally balanced.

Just 1 PSI over atmospheric in the pipe would probably toss that around like that quite nicely if it wasn't properly vented.

Manhole covers weigh about 250 pounds. That's some serious air from run off...

Solar micro nova

Its the volume, not the pressure.
Think of air pressure volume as a volume of water the same size.
Floating the cover. If the covers don't give then something else does.

Workin like a topper for an old pressure cooker.

I must be pretty damn tuff then

Used to heave them around all day

Seriously I think more like a stout hundo

Which is still a lot

You could be right

They are different sizes so different weights too

that was cool.

i'll bet it was loud too

I like how you think

Hutchison effect !!!!!


Russia probably got all their scalar facilities on high power at this critical moment

something big should occur near where that manhole cover was very soon

Manhole is sexist.

Bang my manhole, bro!

Looks like the guy who missed his flight to the farting contest in India just had to really let it all go. He would obviously have won, for sure.

Bullshit. I removed them at 10 years old and they aint no damn 250 pounds! They ARE heavy, solid iron, more like 75-100 pounds.
Jeez

Maybe partially blocked and the surges push the air out faster than it takes to refill the void.

^glad to see someone knows physics.

its happy?

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