A cigarette is standing vertically on its butt. You cannot touch it with any object(solids, liquids or gases). That goes for the foundation also. How can you make it drop? Asking another person to do it does not count.

(In reply to thought by einstein)

Einstein, the sound wave indeed needs a medium to travel through.  No medium (as in space) means no sound. 
A sound wave is in fact the (momentarily) change in local density of the medium on every point of the path of the sound wave.  So the medium must move in order to propagate the sound wave.  The movement of the medium (in this case presumably air) would make the cigarette to fall, which is not allowed by the problem.
Without doing any calculations, I guess this would be very huge books you where going to bang.

Posted by Hugo on 2005-01-13 20:40:18