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A distracted driver is travelling at 65mph on a roadway with an upgrade of 4% before he finally notices a wreck up ahead that has a stopped the flow of traffic. The driver
begins braking at a distance of 270 feet before the site of the wreck the last 150 feet of roadway before the wreck is dry and poor condition, while the 120 feet of roadway before that is dry and in good condition. The vehicle has braking efficiency of 85%.Three vehicles ahead of the driver have been stopped by the wreck, each vehicle being 20 feet long and spaced at 10 feet. The first vehicle is also stopped at 10 feet before the site of the wreck. Will the driver be able to stop in time before hitting the nearest vehicle in front of him? (Assume theoretical stopping distance, ignore air resistance and let frl=0.015)
Given,
Initial speed, Vi = 65 mph or 95.33 ft/s
Grade, G = 4% or 0.04
Rolling resistance factor, frl = 0.015
Braking efficiency, = 85%
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