Student or Learner
I'm sorry this might be a scientific question, but from the standpoint of common sense by native speakers, what the tiny tube of air do you think is made of? I mean, does the tube have the surface of water covering all around or without water? Is it an empty air itself? If it is, how can it be differed or separated from the outer air? I'm sorry.
ex)You can make air move faster than the speed of sound by doing a simple trick; throw a rock in a pond. In a recent study, researchers showed that as a rock falls into a flat surface of water, it carves out a tiny tube of air. This tube connects the sinking rock to the air above the pond. The tube doesn't exist for very long, though- almost immeidately, the surrounding water pushes on the sides. This pressure is stronger in the middle than at the ends. As a result, the tube looks like an hourglass, where the middle gets smaller as the water forces the air out. There's no room in the hourglass for water and air,so as the water comes in the air escapes. These jets of air can blast faster than the speed of sound, the scientists, found.
Last edited by keannu; 30-Nov-2011 at 10:27.
I don't think a tube is created.
I believe that a tube-shaped bubble of air is created by the displacement of water as the rock falls onto its flat surface, begins to sink and forces air upwards.