PRINCIPLES OF HIGHWAY ENGINEERING+TRAFF
7th Edition
ISBN: 9781119688372
Author: Mannering
Publisher: WILEY
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Question
Chapter 2, Problem 27P
To determine
The minimum distance from the stalled car at which the driver could apply the brakes and still stop before hitting it.
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A driver is traveling 70 mi/hr on a road with a -2% downgrade. The driver's vehicle has a
braking efficiency of 90% and has anti-lock brakes. There is a stalled car on the road 500 ft
ahead of the driver. The road is in good condition and is initially dry, but is wet for a 200 ft
stretch just before the stalled car. What is the maximum allowable perception-reaction time
of the driver such that she can still stop before hitting the stalled car? (Assume theoretical
stopping distance, ignore air resistance, and let fri = 0.013.)
2-A motorist travelling at 100 km/h on a highway needs to take the next
exit, which has a speed limit of 50 km/h. The section of the roadway
before the ramp entry has a downgrade of 3% and coefficient of friction f
is 0.35. In order to enter the ramp at the maximum allowable speed limit,
find the braking distance (expressed in m) from the exit ramp.
a truck was travelling uphill at 50kph. the brakes are suddenly applied and the truck stopped in a distance of 16.1m. if the coefficient of friction between the tires and the road surface is 0.4, what is the grade of the road?
Chapter 2 Solutions
PRINCIPLES OF HIGHWAY ENGINEERING+TRAFF
Ch. 2 - Prob. 1PCh. 2 - Prob. 2PCh. 2 - Prob. 3PCh. 2 - Prob. 4PCh. 2 - Prob. 5PCh. 2 - Prob. 6PCh. 2 - Prob. 7PCh. 2 - Prob. 8PCh. 2 - Prob. 9PCh. 2 - Prob. 10P
Ch. 2 - Prob. 11PCh. 2 - Prob. 12PCh. 2 - Prob. 13PCh. 2 - Prob. 14PCh. 2 - Prob. 15PCh. 2 - Prob. 16PCh. 2 - Prob. 17PCh. 2 - Prob. 18PCh. 2 - Prob. 19PCh. 2 - Prob. 20PCh. 2 - Prob. 21PCh. 2 - Prob. 22PCh. 2 - Prob. 23PCh. 2 - Prob. 24PCh. 2 - Prob. 25PCh. 2 - Prob. 26PCh. 2 - Prob. 27PCh. 2 - Prob. 28PCh. 2 - Prob. 29PCh. 2 - Prob. 30PCh. 2 - Prob. 31PCh. 2 - Prob. 32PCh. 2 - Prob. 33PCh. 2 - Prob. 34PCh. 2 - Prob. 35PCh. 2 - Prob. 36PCh. 2 - Prob. 37PCh. 2 - Prob. 38PCh. 2 - Prob. 39PCh. 2 - Prob. 40P
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