Highway Engineering test on “Traffic Regulation and Control”.
1. To reduce the conflict points which method is preferable?
a) Restricting the entry in one side
b) Widening of the roads
c) Use of traffic signals
d) Diverting the traffic
Answer: c
Clarification: In this case, use of traffic signals is advisable as it will be useful to control the traffic up to a certain extent; if it becomes heavy, then diverting may be another option which is not convenient.
2. One of the disadvantages of traffic signals is?
a) Provide orderly moment at intersection
b) The quality of the traffic flow improves
c) Traffic handling capacity increases
d) The rear end collision increases
Answer: d
Clarification: The rear end collisions are common in very highly populated cities, if there is a sudden stoppage of vehicles there is a chance of rear end collision.
3. The traffic signals that are installed for pedestrians are called __________
a) Traffic control signals
b) Pedestrian signals
c) Special traffic signals
d) Automatic signals
Answer: b
Clarification: The signals that are installed for pedestrians are called as pedestrian signals; they are useful when there is no person to control the traffic.
4. The clearance time for amber is usually __________
a) 0.5sec
b) 1sec
c) 1.5sec
d) 3sec
Answer: d
Clarification: The clearance time for amber may be assumed as 2sec to 4 sec, in most of the cities it is assumed as 3 seconds.
5. In trial cycle method, the average time headway is assumed as __________
a) 2sec
b) 2.5sec
c) 3sec
d) 3.5sec
Answer: b
Clarification: The average headway in the trial cycle method is assumed as 2.5sec for 15 minutes of trial cycle.
6. The number of cycles for a trial period of 45 sec is?
a) 20
b) 22
c) 25
d) 30
Answer: a
Clarification: Number of cycles=900/45
=20.
7. If the number of cycles in trial cycle method is 20, for traffic of 170 on one road and 160 on other road, then calculate the total green time in sec.
a) 38
b) 39
c) 40
d) 41
Answer: d
Clarification: Green time on 1st road=170*2.5/20
=21.25
Green time on 2nd road=160*2.5/20
=20
Total green time=41 sec.
8. In approximate method of signals, the average time taken to cross by the pedestrian is?
a) 4sec
b) 5sec
c) 6sec
d) 7sec
Answer: d
Clarification: In approximate method, the time taken is assumed as the crossing time and initial time taken to cross, which should not be less than 7sec.
9. There is a traffic flow of 250 vehicles on road A and 200 vehicles on road B, if the green signal time on road A is 15 sec, then the green signal time of road B is?
a) 10sec
b) 11sec
c) 12sec
d) 13sec
Answer: b
Clarification: From the relationship,
Ga/Gb=na/nb
Ga/Gb=250/200
Gb=12sec.
10. If the amber time at a signal is 3 sec and the green signal time is 25sec, find the red signal time?
a) 22sec
b) 21sec
c) 28sec
d) 29sec
Answer: c
Clarification: The total red time is the sum of green time and amber time, so total red time=25+3=28sec.
11. Which of the traffic signal method is based on saturation flow?
a) Trial cycle method
b) Webster method
c) IRC method
d) Approximate method
Answer: b
Clarification: The saturation flow is the maximum flow which occurs on the peak hours and it is the maximum flow, in absence of data it is assumed as 1600PCU.
12. On a 2 phase road, the saturation flow on road A is 1000 and normal flow is 250,whereas on road B the saturation flow is 1500 and normal flow is 500,the total red time is 10 sec, find optimum cycle length.
a) 35sec
b) 36sec
c) 37sec
d) 38sec
Answer: c
Clarification: Ya=250/1000=0.4
Yb=500/1500=0.3
Y=Ya+Yb=0.7
C0=1.5*L+5/ (1-Y)
C0=1.5*14+5/ (1-0.7)
C0=87sec.
13. Which type of traffic island can be used for reduction of conflict point?
a) Divisional Island
b) Channelized Island
c) Pedestrian Loading Island
d) Rotary Island
Answer: d
Clarification: The major conflicting points can be mostly reduced by rotary islands, which are mostly used near major traffic intersections.
14. The indicators that may be marked for visible outline of the road is called __________
a) Roadway indicator
b) Roadway delineator
c) Roadway line
d) Roadway markings
Answer: b
Clarification: The indicators that are marked for the visible outline are called as roadway indicators, they are of 3 types they are roadway indicator, hazard makers and object markers.
15. The guide posts are usually of height?
a) 0.6m
b) 0.7m
c) 0.8m
d) 2.0m
Answer: c
Clarification: The guide posts are usually of height 0.8-1.2m and they are placed at 45 degree angle for clear visibility.