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12-13. Tests reveal that a normal driver takes about 0.75
Chapter 12, Problem 12-13(choose chapter or problem)
12-13. Tests reveal that a normal driver takes about 0.75 s before he or she can react to a situation to avoid a collision. It lakes about 3 s for a driver having 0.1% alcohol in his system to do the same. If such drivers are traveling on a straight road at 30 mph (44 ft/s) and their cars can decelerate at 2 ft/s2, determine the shortest stopping distance d for each from the moment they see the pedestrians. Moral: If you must drink, please don't drive!
Questions & Answers
QUESTION:
12-13. Tests reveal that a normal driver takes about 0.75 s before he or she can react to a situation to avoid a collision. It lakes about 3 s for a driver having 0.1% alcohol in his system to do the same. If such drivers are traveling on a straight road at 30 mph (44 ft/s) and their cars can decelerate at 2 ft/s2, determine the shortest stopping distance d for each from the moment they see the pedestrians. Moral: If you must drink, please don't drive!
ANSWER:Step 1 of 7
The origin is at point O with the positive motion to the right.
Given that the acceleration is known and constant, we can use expression (12-4) to determine time needed for the car to slow down from 
