Wednesday, October 9, 2013

SCIENCE NEWS - BULLETPROOF VEST #22

Wonder Contributors

Today’s Wonder of the Day was submitted to us by our Wonder Friend Tyler of Monroe, Ohio.  As of today, Tyler’s Wonder has received 272 votes! Way to go, Tyler! Keep WONDERing with us! 
If you’re thinking of a future career in the military or as a police officer, there’s an article of clothing you will probably have to get used to wearing. No, we’re not talking about a uniform. Yes, there are certainly uniforms to be worn, but we’re talking about something that protects you from danger: the bulletproof vest!
If you’ve seen a television show about police, a war movie, or even the nightly news in the recent past, you’ve probably seen bulletproof vests. Worn for safety and protection, these often life-saving articles of clothing are meant to prevent death or serious injury from a wide variety of dangers, including bullets.
Those same movies and television shows have probably made it clear to you just how dangerous bullets can be. They’re meant to be deadly and they often are. For the people who protect our country and communities, though, they don’t have to be. Thanks to modern technology, even the mighty bullet can be stopped!
You’re probably WONDERing exactly HOW bulletproof vests stop bullets. After all, they have to be worn by people who often have to move around quickly. It’s not like they can wear a brick wall around themselves! No, they need “soft” body armor that is lightweight and flexible enough to allow easy movement.
To understand how these types of bulletproof vests work, it might help if you’re a soccer player. What? It’s true! Like the net on a soccer goal catches and stops a soccer ball — even one kicked by the likes of Cristiano Ronaldo or Lionel Messi — bulletproof vests contain web-like nets of special fabrics that stop bullets (or shrapnel or blades).
Like a soccer goal’s net absorbs the ball’s energy and spreads it out across all the fibers in the net, effectively slowing and then stopping the ball’s forward movement, the tightly-wovenflexible synthetic fibers in a bulletproof vest do the same thing. The fibers in the vest “catch” the bullet and bring it to a stop before it can penetrate the body and cause serious injury or even death.
If you’ve ever seen a soccer ball kicked into a goal, you know that the net gives way and allows the ball to travel a little ways before it stops it and brings it to the ground. Bulletproof vests cannot give that much, however.
That’s why the fibers in a bulletproof vest must be packed together much more tightly. They’re so densely packed that you could think of them as multiple soccer goal nets overlapped and piled on top of each other — thousands and thousands of times over in a tiny space.
That’s where the modern technology of synthetic fibers comes into play. As early as 1965, chemical company DuPont manufactured a synthetic fiber known for its high strength, low weight, and resistance to chemicals, cuts, and fire. This fiber — called Kevlar — was soon used to make the first generation of flexible, concealable body armor.
Since that time, DuPont and other companies have created a wide variety of such synthetic fibers. But guess what might be the fiber of the future? Would you believe genetically-modified spider silk? Maybe!
Today’s bulletproof vests will protect against most common low-caliber handguns, but high-powered weapons, especially rifles, can still penetrate bulletproof vests. The only protection from these types of weapons is usually “hard” bulletproof armor made of rigid ceramics and metals. Unfortunately, these types of body armor are usually too bulky and heavy to wear for everyday use.
- See more at: http://wonderopolis.org/wonder/how-do-bulletproof-vests-work/#sthash.kBK3q0yR.dpuf