suction

Clingfish (Gobiesox maeandricus).Image credit: Thomas Kleinteich Live Science posted a story recently on the sticking power of clingfish. Northern clingfish, like the one shown in the image above, live in turbulent waters off the Pacific Coast of North America. In order to cling to surfaces, the animals have what are called adhesion discs on their bellies that they use to hold on tightly to various surfaces. Biologist Adam Summers at the University of Washington has been studying how these fish cling to surfaces. His research team put a variety of sandpaper textures into a tank of water…
How does a suction cup work? It is all about the atmosphere. Here is a demo. Take some type of "suction cup" device. In this case, I used a toy dart. Stick it to something smooth and lift it up. Like this: What lifts up the metal block? The atmosphere. Diagram time: But this isn't a very realistic diagram. Actually, the suction cup would be pushing down on the block because the force from the atmosphere would be too large to balance with the weight. Let me put some numbers in here. Suppose this is an aluminum block - I just going to pretend it is 4cm on a side (and a cube). In…
Check out this thing. That is where the guy (Jem Stansfield of BBC's Bang Goes the Theory) shows how he built this thing. Here is part 2 where he uses it to climb a building. Here are some questions: Why does it not matter how powerful the vacuum is? How does a vacuum cleaner work anyway? How does the vacuum cleaner work? I know this is not HowStuffWorks.com, but I guess I should show some stuff. The cool thing about a vacuum cleaner (think shop vac so that I don't have to deal with the brushes) is that it is just one thing - a fan. The fan essentially moves air out of the vacuum part of…