PRINCIPLES OF HIGHWAY ENGINEERING+TRAFF
7th Edition
ISBN: 9781119688372
Author: Mannering
Publisher: WILEY
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Question
Chapter 2, Problem 28P
To determine
The value of feet it will take the car to stop from the point of initial brake application.
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A car is traveling at 70 mi/h on a level section of road with good, wet pavement. Its antilock braking system (ABS) only starts to work after the brakes have been locked for 100 ft. If the driver holds the brake pedal down completely, immediately locking the wheels, and keeps the pedal down during the entire process, how many feet will it take the car to stop from the point of initial brake application? (The braking efficiency is 80% with the ABS not working and 100 % with the ABS working. Use theoretical stopping distance and ignore air resistance. Let frl = 0.02 when the brakes are locked, but complete the frl once the ABS becomes active.)
A race car with a 106-inch wheelbase has its weight evenly distributed between front and rear axles. At 150 mi/h, on a race track with = 1.0, the optimal brake force has 67.32% of the braking force on the front brakes. A new racing tire generates = 1.2. At 150 mi/h, what percentage of the braking force should now be allocated to the front to achieve optimal braking?
The car is traveling at 48 km/h when the traffic light 90 m
ahead turns yellow. The driver
takes one second to react
before he applies the brakes.
(a) After he applies the brakes,
what constant rate of
deceleration will cause the car
to come to a stop just as
it reached the light?
(b) How long does it take the
car to travel the 90 m?
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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