Have you ever noticed

[pscot]

that when you rotate your coffee cup, the coffee inside doesn't turn with the cup? Must be physics, or something.

[NV Whino]

1. Yes, but in Australia it doesn't turn in the opposite direction.

[pscot]

2. Only because it's upside down

[NV Whino]

3. Good point.

[dixiegrrrrl]

4. whereas in China it falls out of the cup....

[patricia92243]

18. lol!!

[2naSalit]

19. DUzy!!!

[DryHump]

5. Zero friction

between liquid and porcelain of the cup? Any science geeks out there?

[mackerel]

6. Now I want a cuppa

[Major Nikon]

7. The bowl doesn't turn when you flush either

[olddots]

8. Avoid the puple acid

[pscot]

14. I once had a thousand of those

Oddly, I can't recall what color they were.

[kentauros]

9. Freeze it.

Then get back to us with the results.

[LiberalEsto]

10. Help is on the way!

[pscot]

12. That's the oldest trick in the book.

There must be a little propeller thingy in there. While taking my fist sip of that roboratve brew, My mustache gets caught in there and I'm dragged to a highly caffeinated death. Nice try, buddy, but I see through your nefarious scheme.

[LiberalEsto]

15. mwa ha ha ha haa

[Enthusiast]

22. Really? That's a thing?

I had no idea.

[BlueJazz]

11. I experimented with your observation by attaching the cup to my Lawn Mower blade.

The water actually does turn at 2300 RPM. The cup went somewhere over the neighbors fence. I'm not going to look for it...

[pscot]

13. You need a much finer grind

Escape velocity is 7 miles a second.

[BlueJazz]

16. Did a little quick math in my head. If I can get the mower up to about 2,625,000 rpm I,...

...just might be able to accomplish that feat.
Houston, I need a very large lawn mower, gears and....oh..a titanium coffee cup.

[discntnt_irny_srcsm]

17. It's called conservation of angular momentum

[Wounded Bear]

20. Actually, I think it's inertia...

Newton's first law of motion and all that.

[discntnt_irny_srcsm]

21. Conservation of angular momentum is a specific instance of...

...the general principle of inertia. I was a physics major.
Objects at rest tend to remain at rest unless acted upon by an outside force.
If you rotate the cup enough the coffee will begin to move with it.

[JustABozoOnThisBus]

23. I'd check on that, except my body is currently at rest ...

... and it's tending to stay that way.

[discntnt_irny_srcsm]

27. at rest...

In the beginning there was Aristotle,
And objects at rest tended to remain at rest,
And objects in motion tended to come to rest,
And soon everything was at rest,
And God saw that it was boring.

Then God created Newton,
And objects at rest tended to remain at rest,
But objects in motion tended to remain in motion,
And energy was conserved and momentum was conserved
and matter was conserved,
And God saw that it was conservative.

Then God created Einstein,
And everything was relative,
And fast things became short,
And straight things became curved,
And the universe was filled with inertial frames,
And God saw that it was relatively general,
but some of it was especially relative.

Then God created Bohr,
And there was the principle,
And the principle was quantum,
And all things were quantified,
But some things were still relative,
And God saw that it was confusing.

Then God was going to create Furgeson,
And Furgeson would have unified,
And he would have fielded a theory,
And all would have been one,
But it was the seventh day,
And God rested,
And objects at rest tend to remain at rest.

[seveneyes]

24. Friction, when water becomes sand ...

[pscot]

25. I'm glad to learn

there's a study group working this problem. Have you read Seveneyes? I'm, like, 143rd on my library waiting list

[seveneyes]

26. I read mostly music

and write mostly abstract vernacular.

[qnr]

28. That's because coffee is awesome, and starts stealing your asleepednessification

before you even start drinking it. So it's asleep when you turn the cup, and isn't able to follow it around.

[pscot]

29. See! I knew it was physics.