Whatever floats your cups

Factual Questions
1

What is happening here? I went into the kitchen at work today and grabbed a styrofoam cup off a stack of them that is inverted. When I did, the cup below it rose up ~3/4 of an inch and stayed there.

I think I’ve seen this before and had just thought it was lodged against the wall, or, more likely, just didn’t think about it. But today I noticed that it was not touching the wall, or anything else. It was just floating above the next cup in the stack. I pushed it down with my finger and met no resistance.

Perplexed, I repeated this several times, and got similar results - not always 3/4", sometimes 1/2", sometimes 1/4". And these cups were not just temporarily lifted by vacuum created by removal of the cup above (although I’m sure that’s part of the phenomenon) and then settling back down. The cups would stay in the elevated position until I pushed 'em back down, or pulled 'em off the stack to see the next one do it. I watched one of the 3/4" floaters for 10 minutes (yeah, I’ve got to review every project I’m working on with our CEO on Thursday and I’m watching floating cups - I may have a lot more time to spend on the board soon) and it never began to settle.

So, I pull upside down styrofoam cups off of a stack of them and the next one rises a bit and appears to remain in position without any solid physical support. I’ve pondered it a bit and started cooking up some not very successful hypotheses involving vacuum (involved initially, I’m sure), static electricity and and air temperature or pressure.

But, as I say, I’ve not strung together any satisfying conclusions. Anyone?

2

Static electricity would be my guess.

But maybe you should put on the tinfoil hat and try it again…

:smiley:

3

My tinfoil hat doesn’t fit.

Any other takers?

4

Almost certain it’s static electricity. Every open a box containing styrofoam peanuts and had them
stick to everything? I would guess that the process of taking a cup off the stack generates a charge
on the cups below it which doesn’t dissipate because styrofoam is a pretty good insulator. Because the cups have the same charge, they repel each other.

5

Don’t let anyone discourage you, you obviously have the secret talent of levitation. :smiley:

6

Floating cups, eh?

“Waitress, I’ll have whatever he’s having.”

7

It’s static electricity.

I had this happen to me the other day, I dragged two cups instead of one off the top of the stack. When I went to replace the extra, I dropped it on the stack just to have it bounce back up and flip off the stack all together. I got it to do that a couple of times before I exhausted the entertainment value and just stuffed it tightly back on the stack.

-B