Another puzzle
 

In the spirit of the plane-on-a-treadmill puzzle, I ask you this:

would a siphon work on the moon?

Inside a lunar lander with atmosphere, yes. But slower.

Outside, assuming we have a fluid that stayed liquid in that environment, my guess is that it would work if you got it started, but the usual way to start it would not work.

Once it is going, I think it is powered by gravity and surface tension (which may again be affected by the fluid being used).

You wouldn't be able to start it by sucking air out of the tube. Maybe if you started with the tube fully submerged, and then pulled one end over the side.

Ahh, but what fluid would remain liquid, rather than immediately boiling away due to zero atmosphere? And wouldn't the boiling produce gas bubbles that would break up the siphoning effect?

Would a toilet flush on the moon?

and if so, which way would the water swirl?

No it won't work because you didn't pay your bill.

If you sucked bad enough, no. :)

From your favorite source of all things informational:
Vacuum siphons

Experiments have shown that siphons can operate in a vacuum, provided that the liquids are pure and degassed and surfaces are very clean.[31][32][33]
[edit] Oxford English Dictionary

The Oxford English Dictionary (OED) entry on siphon, published in 1911, states that a siphon works by atmospheric pressure. Stephen Hughes of Queensland University of Technology criticised this in a 2010 article[9] which was widely reported in the media.[34][35][36][37] The OED editors stated, "there is continuing debate among scientists as to which view is correct. ... We would expect to reflect this debate in the fully updated entry for siphon, due to be published later this year."[38] Dr. Hughes continued to defend his view of the siphon in a late September post at the Oxford blog.[39]

It doesn't matter, I'm pretty sure Jack Schmitt forgot to fill up the rover after his joy-ride. Some kids are just irresponsible.

I'm not sure, but as you can see, I assumed that complication away.

If there is no liquid that can remain so in a vacuum, then of course you can't siphon one. And you probably couldn't maintain a siphon for very long on a liquid that is in the process of boiling or freezing.

But I'll stick with my answer if the liquid exists (and footfootfoot's wikipedia link seems to say it does).

Perhaps a siphon filled with mercury, set up on the surface of the moon in the sunshine. Mercury's freezing point is lower than the average daylight surface temperature of the moon. I doubt mercury has dissolved gas in it.

BigV's proposed tube of mercury might be modified with a semi-permeable membrane to allow a strange form of osmosis to occur. Maybe it's not a true "siphon" but it might move something from one place to another (in any direction)

Never mind that shit, here comes Mongo!!

I'm resurrecting this old thread to post this puzzle.

No Google. No cheating.

What do these mean? (I haven't seen an answer key, but I got 5 of them so far. I'm sure there has to be an answer key out there, since I saw this on FB)

Attachment 38086

Wait. I know them all except the bottom right one.