notes-and-tea: fuckyeahphysica: How do zippers work? * How are…

notes-and-tea:

fuckyeahphysica:

How do zippers work?

* How are zippers made ?

** Lego zipper

Someone explain how they unzip

How do they unzip?

When you are chopping vegetables or splitting a log of wood, this is basically what is happening ( I leave you to do the FBD on this for more clarity )

The wedge (axe or a knife) not only slices through the object but also exerts a perpendicular force that pushes it outward.

This is exactly what happens while unzipping as well. A wedge is placed on the zipper that splits the two rows of interlocked teeth. 

Pretty cool right ?