PRINCIPLES OF HIGHWAY ENGINEERING+TRAFF
7th Edition
ISBN: 9781119688372
Author: Mannering
Publisher: WILEY
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 2, Problem 37P
To determine
The percentage braking force that the braking system should allocate to the rear axle.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A car traveling at 45 mph on a poor, wet pavement has a braking efficiency of 87%. The
brakes were applied 100 feet before hitting an obstacle in the road. The road is uphill for 40
feet and then is level for the remainder of the way. The car had a maximum coefficient of
road adhesion in the sloped portion of the poor, wet roadway and but as soon as it started
going on the level portion its coefficient of road adhesion reduced to 0.3. Assuming that the
car struck the obstacle at 30 mph, what was the grade of the hill? Assume practical stopping
distance equation applies.
8 ft wheelbase
Rear-wheel drive
Center of gravity 17 inches above the road 4.1 ft behind the front axle.
The car weighs 2500 lb
Mechanical efficiency of the drivetrain is 93%
Wheel radius is 14 inches.
If the engine develops 190 ft-lb of torque and the overall gear reduction ratio is 7
to 1, what is the maximum acceleration from rest for the car? Assume good, dry,
and level pavement conditions.
6 A car is traveling at 20 mi/h on good, dry pavement at 5000 ft elevation. The front-wheel-drive car has a drag coefficient of 0.30, a frontal area of 20 ft2 and a weight of 2500 lb. The wheelbase is 110 inches and the center of gravity is 20 inches from the ground, 50 inches behind the front axle. The engine is producing 95 ft-lb of torque and is in a gear that gives an overall gear reduction ratio of 4.5. The radius of the drive wheels is 14 inches and the mechanical efficiency of the drivetrain is 90%. What would the acceleration of the car be if the driver was accelerating quickly to avoid a collision?
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
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, civil-engineering and related others by exploring similar questions and additional content below.Similar questions
- Please provide correct solutionarrow_forward1. The driver of a vehicle traveling at 80 kph up a grade requires 9 m less to stop after he applies the brakes than the driver travelling at the same initial speed down the same grade. If the coefficient of friction between the tires and pavement is 0.50, what is the percent grade and what is the braking distance down the grade. V,=80 kph V2=0 brakes are applied S-9 V,=80 kph V2=0 brakes are applied -S-arrow_forwardIn a certain situation it was estimated that 25% of the braking force was applied to the rear brakes in order for the car to develop the maximum forces required stop the car. If the total braking force developed was 5565 N and the road is wet (u = 0.6), wheelbase of 295 cm and a center of gravity 75 cm above the pavement and 120 cm behind the front axle. Determine the weight of the vehicle (N)arrow_forward
- In a certain situation it was estimated that 25% of the braking force was applied to the rear brakes in order for the car to develop the maximum forces required stop the car. If the total braking force developed was 5000 N and the road is wet (u = 0.52), wheel base of 290 cm and a center of gravity 64 cm above the pavement and 120 cm behind the front axle. Determine the weight of the vehicle (N).arrow_forwardA car is traveling at 76 mi/hr down a 3% grade on poor, wet pavement. The car's braking efficiency is 90%. The brakes were applied 320 ft before impacting an object. The car had an antilock braking system, but the system failed 200ft after the brakes had been applied (wheels locked). What speed was the car traveling at just before it impacted the object? (Assume theoretical stopping distance, ignore air resistance, and let Frl=0.015)arrow_forwardDetermine the horsepower developed by a passenger car traveling at a speed of 50-mi/h on an upgrade of 5% with a smooth pavement. The weight of the car is 4,500-lb and the cross-sectional area of the vehicle is 50 square-feet. Repeat this for a 24,000-lb truck with cross-sectional area of 100 square-feet and coefficient of drag of 0.5 traveling at 55-mi/h.arrow_forward
- A rear-wheel-drive 2800-lb drag race car has a 170-inch wheelbase and a center of gravity 20 inches above the pavement and 140 inches behind the front axle. The owners wish to achieve an initial acceleration from rest of 22 ft/s 2 on a level paved surface. What is the minimum coefficient of road adhesion (in %) needed to achieve this acceleration? (Assume y m = 1.00.)arrow_forwarda 2500-lb car designed with a 120-inch wheelbase. the center of gravity is located 22 inches above the pavement and 40 inches the front axle. if the coefficient of road adhesion is 0.6, how far back from the front axle would the center of gravity have to be to ensure that the maximum tractive effort developed for front- and rear- wheel-drive option is equal?arrow_forwardCompute the braking distance for a car moving at an initial velocity of 60kph and a final velocity of 40 kph. slope of roadway is +5% Coefficient of friction between the pavement and tires = 0.15 perception-reaction time = 3/4 secarrow_forward
- O-A vehicle is moving on a road of grade +4% at a speed of 20 m/s. Consider the coefficient of rolling friction as 0.46 and acceleration due to gravity as 10 m/s2. On applying brakes to reach a speed of 10 m/s, Find the required braking distance (in m, round off to nearest integer) along the horizontal.arrow_forwardHelp mee pleasee. Complete solutionarrow_forwardA 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.)arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Structural Analysis (10th Edition)Civil EngineeringISBN:9780134610672Author:Russell C. HibbelerPublisher:PEARSON
Principles of Foundation Engineering (MindTap Cou...Civil EngineeringISBN:9781337705028Author:Braja M. Das, Nagaratnam SivakuganPublisher:Cengage Learning
Fundamentals of Structural AnalysisCivil EngineeringISBN:9780073398006Author:Kenneth M. Leet Emeritus, Chia-Ming Uang, Joel LanningPublisher:McGraw-Hill Education
Traffic and Highway EngineeringCivil EngineeringISBN:9781305156241Author:Garber, Nicholas J.Publisher:Cengage Learning
Structural Analysis (10th Edition)
Civil Engineering
ISBN:9780134610672
Author:Russell C. Hibbeler
Publisher:PEARSON
Principles of Foundation Engineering (MindTap Cou...
Civil Engineering
ISBN:9781337705028
Author:Braja M. Das, Nagaratnam Sivakugan
Publisher:Cengage Learning
Fundamentals of Structural Analysis
Civil Engineering
ISBN:9780073398006
Author:Kenneth M. Leet Emeritus, Chia-Ming Uang, Joel Lanning
Publisher:McGraw-Hill Education
Traffic and Highway Engineering
Civil Engineering
ISBN:9781305156241
Author:Garber, Nicholas J.
Publisher:Cengage Learning