What Caused It??

[horseshoes]

Bit of a daft question really. I was spinning a swizzle stick around my empty tall glass last night, and as it went faster it rose up and flew out of the glass. What is the scientific reason for that? Thanks in advance.

[Davethedog]

Centrifugal force

[squillakid]

Ghosts!

[Foo.King]

no scientific answer really the reason you was spinning a swizzle stick round in a empty glass was simply boredom and small minds are easily amused.




hth

[craft1948]

morning nokno....

[jake-the-peg]

Sounds like it might be a "chaotic system"

Such systems like double pendulums are very sensitive to initial conditions and their movements can amplify in unexpected ways.

This is the "butterfly effect" the idea being that a butterfly's wing beat in New York can trigger a storm in London.

A classic example is a double pendulum - see this simulation:
http://www.physics.usyd.edu.au/~wheat/dpend_ht ml/dpend.gif

It goes back and forth a couple of times and then flips over

You'll probably not do it again though

Look at this simulation

http://www.physics.usyd.edu.au/~wheat/dpend_ht ml/dpend2.gif

Two identical pendulums are super imposed their starting position is a thousanth of a degree different

At first you only see one and then quickly their movements seperate and very soon they have very very different patterns despite having started in almost the same spot

[horseshoes]

Thanks Davethedog.

[Davethedog]

n p :-)

[horseshoes]

Thanks Jake. I'm not small minded as Foo.King suggests, just not that into physics. Those pendulum diagrams are fascinating. It got me wondering about it, because (I don't know how old you are), but I remember a fairground "ride" called the ROTOR, in which about a dozen or so people stood against the wall, and it started to rotate, getting faster & faster until the peole "stuck" to the wall and the floor descended. I wondered why what happened to my swizzle stick hadn't happened on the ROTOR.

[jake-the-peg]

Well it may or may not have been a chaotic system depending on the conditions.

It was possibly that it was spinning and then hit something, the rim of the glass or an icecube. Then that energy that was in the spinning gets converted into lateral motion and it jumps out of the glass.

But certainly things that slow down like a roulette ball or even a stream of smoke breaking up into swirls are classic chaotic systems and your swizzle stick sounds very like that.

The Rotor ride on the other hand spins around and presses you to the wall with, well let's call it centrifugal force. (Technically there's no such thing but that's not important right now, it's a handy shorthand)

that force keeps you well pushed back, as it slows, thats when you could start to see this sort of thing which is why you're strapped in.

Imagine no restraints, as it slows someone light get's unstuck and thrown, they then hit part of the moving ride and are flung like a roulette ball, maybe they cannon onto someone else and....

Well lets say restraints are a good idea!

[horseshoes]

Jake, funnily enough we didn't have restraints!!! The lads used to do tricks like working their way around so that the were upside down, we more timid girls just used to try and move our arms away from the walls - quite an effort. When it slowed down we just slithered down a bit and the floor came up again to meet us. What 'elf & Safety????

[horseshoes]

Yes Tonyted - that's exactly what my husband said too!!! Do you remember how rickety the whole structure was? I wouldn't get in it now for all the tea in China.

[theprof]

Hmm, I remember getting into one of these at Alton Towers with the wife in the late eighties although I can't remember the name of the ride.

As a scientist, I knew all about the theory of centrifugal forces and had utilised them in the lab on many occasions. Believe me, it was something else to experience the force on my own body on that ride and I've never looked upon a centrifuge tube quite the same since then!

[theprof]

I've just remembered that the ride was called The Gravitron.

[wildwood]

Was your glass one of those new fangled plastic ones? It may be that you built up some static electricity and the (plastic?) stick got repelled.

[jake-the-peg]

You mean like this Graviton that injured 7

http://asianfanatics.net/forum/index.php?showt opic=10030&mode=linearplus

There was another incident in Washington but the boy had climbed the rails.

http://en.wikipedia.org/wiki/Gravitron

Provided it slows gently nobody shouls become a human twizzle stick

[ChuckFickens]

is anybody going to pick up on the fact that when you spin something round in a glass your not rotating the glass on it axis (like the rotor as mentioned by the prof) but your wobbling the glass so the side are no longer vertical.

[horseshoes]

The ride was definitely called "The Rotor". It had a wooden frame around it so that if you weren't actually "riding" it, you could go to the top of the wooden frame and look down at the people inside. (This is where the boys used to go to watch, and to see if the girls' skirts rode up - wich they always did unless you tucked it into your knicker legs)!!!! It was best to wear jeans. The one I remember was in Rhyl in the 60s. It really was ramshackle but to my knowledge, nobody was ever hurt on it.

[horseshoes]

Look what I found - this is what it was like, but not so colourful and tidy.

https://www.youtube.com/watch?v=ESRPhGQerNM

[chakka35]

What shape was the glass?

If it was conical - i.e. wider at the top - then as centrifugal force (so-called) tried to push the sizzler further and further out it would inevitably move upwards to get more room, eventually reaching the top.