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Applying Physics
Applying Physics II
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After it is completed by a spider, the entire spider web is under the same tension no matter how far it is stretched or compressed. The radial threads from the center are strong enough to withhold the same force from any point along the web. In this image where a force is represented as an arrow impacting the web, Model of
                      spiderwebthe stiffness and strength of the web remains the same throughout, regardless of how far the force impacts from the center of the web. It has also been found that the adhesive dotted capture thread behaves much like an elastic solid whenever it is stretched. However when it is compressed the adhesive along the web cause the solid silk to spool like a liquid. Even being compressed to 95%, the web remains under the same tension. With the combination of how the spider web is kept under tension and the adhesive silk, spider webs are able to trap insects (rather than them bouncing straight off or destroying the web on impact).

 There is also species of spider that relies on electrically charged webs; orb spiders named Uloborus plumipes. Uloborids are named as cribellate spiders, meaning that they produce wool-like, charged silk rather than the adhesive capture silk that spiders typically spin. The silk is made within the cribellar gland, at a size of 60 micrometers it is among the smallest silk glands ever observed and is covered in microscopic spigots that produce a low-viscosity liquid silk (sciencemag.) Other spiders spin web that is intact from the start however, Uloborus spiders produce silk that is still liquid when it surfaces. This dry capture thread combines thousands of nano-scale filaments to be quickly hackled by feather-like hairs on the spider's legs and electrically charged in the process. This is all possible because Uloborus spiders have one of the most complex silk glands known as of yet, consisting of six different silk systems.
In conclusion, the hackling applied to the web stretches and freezes the fibers into shape, and is likely responsible for strengthening them as nano-scale filaments are strengthened after being stretched (sciencemag.) To charge the silk, the spider pulls it over the feathered hairs on its hind legs (which will also give the web a wool-like appearance.)  The electrically charged silk will theoretically attract prey to the web as any charged object will attract another object that is oppositely charged.