5 will be the only one that will ever fill up unless you really crank up the pressure in which case 7 will also fill but very slowly. 5 and 7 are open containers and there's a hole in the bottom of 4. But if it's water coming out of a tap then only 5 will fill .

[–] [email protected] 17 points 3 days ago (3 children)

The connection between 2 and 3 is blocked.

[–] [email protected] 1 points 10 hours ago

Didn't notice that.

[–] [email protected] 4 points 3 days ago

Damn, I didn't even notice that.

[–] pingveno 3 points 3 days ago

Even if you assume that it is not blocked, it is still 5. The pipe from 2 to 3 is never reached because 4 leaks out the hole in the bottom. Assume that the hole in the bottom is a flaw and 4 still leaks out the top before the pipe to 3 is reached.

[–] [email protected] 4 points 3 days ago (1 children)

1 can also fill up if the flow from the faucet is higher than what can exit through the pipe connecting to 2.

[–] Seasm0ke 1 points 3 days ago (1 children)

There it is!!! That connector is too narrow, only way it isnt 1 is if the pressure is criminally low.

[–] [email protected] 1 points 10 hours ago

Someone's never been to the UK... But also the volume of 5 is significantly less than 1.