Bulletproof vests are meant to protect you from bullets and hand grenades. These vests are made to minimize blood force trauma. The latest vests employ overlapping super-strength but lightweight composites of ceramic and titanium. It blocks bullets because the material inside of the the vest can withstand the force of a bullet and kind of absorb it.
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This relates to engineering because they design the vest to do a certain task. That task is to reduce the amount of blood force trauma when shot. It is also designed for a specific purpose for action in the military or the police.
