Take a glass that is partially filled with water and drop a cork into it. The cork won't float in the center, but keeps drifting to one side and attaching itself to the side of the glass.

\-------------------/
 \                 /
  \##-------------/
   \             /
    \           /
     \         /
      \_______/

Without swirling the water, how can you make the cork float in the center?

Of course, the easiest way to do it would be to freeze the water- although to instantly freeze it you would need extremely low temperatures, down around       -100C, and thats not a temperature you find in your average freezer.

Secondly, you can cut the cork in half, as the two halves attract each other... here you have to assume that they aren't both going to float to the same side, because then this wouldn't work at all.

Finally, (and I'm sure someones said it in a comment below- I'll have a read), Surface Tension. Slightly overfill it, (it won't overflow due to surface tension), and the cork will float up to the centre, as it is the highest point (which is also why it usually floats to the sides- they are usually the highest point, also due to surface tension).

(EDIT: I wanted my minus sign to be next to the 100 rather than on the end of the line =D)

Edited on October 24, 2007, 6:03 pm

Edited on October 24, 2007, 6:03 pm

Edited on October 24, 2007, 6:03 pm

Posted by Matt on 2007-10-24 18:02:40