The total time needed to bring a car to stop after the driver perceives danger is the reaction time plus the braking time. Reaction time is the time between the perception of danger and applying the brakes, and braking time is the time for stopping after applying the brakes. The table below gives the stopping distance d (in feet) of the car traveling at speeds v (in miles per hour) from the instant of danger perception. a. Fit a least squares 2nd degree polynomial of the form d = a, + a1v + azv² b. Estimated when v = 45 mph

The total time needed to bring a car to stop after the driver perceives danger is the reaction time plus the braking time. Reaction time is the time between the perception of danger and applying the brakes, and braking time is the time for stopping after applying the brakes. The table below gives the stopping distance d (in feet) of the car traveling at speeds v (in miles per hour) from the instant of danger perception. a. Fit a least squares 2nd degree polynomial of the form d = a, + a1v + azv² b. Estimated when v = 45 mph

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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7) In studying of traffic flow at a highway toll booth over a course of 60 minutes, it is determined that the arrival and departure rates are deterministic, but not uniform. The arrival rate is found to vary according to the function A(t) = 1.8+0.25t - 0.00312. The departure rate function is u(t) = 1.4 +0 .1lt. In both of these functions, t is in minutes after the beginning of the observation and (t) and „u(t) are in vehicles per minute. At what time does the maximum queue length occur? a) 49.4 min, b) 2.7 min ,c) 19.4 min, d) 60.0 min
SITUATION The data presented in the table illustrates traffic density-speed information gathered from a segment of a highway. If we assume the Greenberg model describes this data, employ linear regression analysis to ascertain the following: Density, k (vpm) 100 92 84 75 70 64 60 54 42 35 28 22 Speed, u, (mph) 20 21 25 27 29 33 35 38 41 46 53 61 determine: Density at maximum flow in veh/mi. Express answer into two decimal places. Do not type the unit. veh/mi
Question 1 In studying traffic flow at a highway toll booth over a course of 60 minutes, it is determined that the arrival and departure rates are deterministic, but not uniform. The arrival rate is found to vary according to the function of A (t) = 1.8 2 +0.25t -0.0030t. The departure rate function is u(t) =1.4 + 0.11 t. In both of these functions, t is in minutes after the beginning of the observation and X(t) and u(t) are in vehicles per minutes. (i) When will the queue that forms be cleared? (ii) What time does the maximum queue length occur and what will be the corresponding queue length? (iii) Determine the total delay (iv) Estimate the average time delay per vehicle
Situation 1: Two automobiles A and B are approaching each other in adjacent highway lanes. At t = 0 seconds, A and B are 1 km apart, their speeds are VA = 110 kph and VB = 60 kph and they are at points P and Q respectively. Knowing that A passes point Q, 40 seconds after B was there and that B passes point P, 42 seconds after A was there. Question 6 Question 7 Question 8 Determine the time when they pass each other. Determine the speed of B when they pass each other. Determine the acceleration of A. 25.89 sec O 24,88 m/s O 0.139 m/s^2 O 20.89 sec O 25.12 m/s O -0.278 m/s^2 O 10.89 sec O 23.77 m/s O 0.34 m/s^2 15.89 sec O 22.54 m/s O 0.48 m/s^2
NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part. Three seconds after automobile B passes through the intersection shown, automobile A passes through the same intersection. Given, the speed of automobile A is VA = 95.00 mi/h and automobile B is vg = 50.00 mi/h, respectively. Also, know that the speeds are constant for the automobiles during the encounter. N 70° S + VA vB Determine the distance between the two automobiles 2 s after A has passed through the intersection. The distance between the two automobiles 2 s after A has passed through the intersection is 356.5 ft.
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1. Data on a traffic accident for the past 4 years has accident rate of 10200 per million entering vehicles. The total number of accidents is 900. Find the average daily traffic (ADT) entering the intersection during the 4 years period. 2. A moving vehicle come up to a danger and traveled a distance of 48 meters during the perception –reaction time of 2.67 seconds. Calculate the specific speed of the vehicle in Kph. a. 20 b. 48.97 c. 52.36 d. 64.70 3. The running speed of a vehicle is equal to a. Travel speed + delay b. Travel speed c. travel speed-delay average of travel speed and delay