Physics 30 Car safety has changed dramatically since Karl Benz invented the rst gasoline- powered vehicle in 1885. The rst cars had no safety devices. Drivers had to wear goggles to protect themselves from hitting birds and insects while driving. Windshields were made of plate glass that would shatter into pieces if hit. Today we take it for granted that all ears have seat belts, safety glass, and airbags. There are even cars with multiple airbags, night vision systems, back up cameras andfor sonar and cars, such as the Volvo XC60, that will stop themselves to prevent collisions. Car designers, scientists, and engineers are even working on cars that will drive themselves in the future. \"'Most of the improvements in safety are the result of crash test information that comes - from crash test dummies. Today's crash test gun-dummies are the culmination of many 5 L E ---decades of testing. From human volunteers to animal cadavers to modern dummies, the technology to simulate dangerous crashes has improved dramatically. Modern dummies come in multiple sizes to simulate humans from small babies up to large adults; they have joints and move like their human counterparts but are full of sensors to measure the accelerations and forces that they experience during a crash to determine how dangerous the collision would be for real people. In a crash test, two test dummies with a mass of 77 kg each are placed in the test vehicle. The driver dummy has a seatbelt while the passenger dummy does not have a seatbelt. The vehicle is placed on a track and run into a wall at 56 kmfh. Upon impact, everything comes to a halt. \"Calculate the impulse for each dummy during the collision. (Analytic '? marks) -The seatbelt brings the driver dummy safely to a halt whereas the passenger stops violently by hitting the dashboard and windshield. Draw a force vs time graph to demonstrate an example set of forces working on each dummy and show that the graphed impulse for each dummy matches the previous calculations. (Graphing 5 marks) ~Describe why the graph for each dummy is different and how those differences show that the driver dummy stops safely and the passenger dummy does not stop safely. (Holistic 5 marks)