Traffic Engineering Multiple Choice Questions on “Basic Freeway Capacity”.
1. Which one of the following is an interrupted facility?
a) Traffic signal
b) Stop sign
c) Yield sign
d) Basic freeway
Answer: d
Clarification: Basic freeway is an interrupted facility. Traffic signal, stop sign an yield sign are external devices which partially interrupts the flow. Some of the interrupted facilities are weaving sections, ramps, and unidirectional multilane highways.
2. Freeway has which magnitude as the measure of effectiveness?
a) Density
b) Speed
c) Capacity
d) Delay
Answer: a
Clarification: Freeway has a density as the measure of effectiveness. Multi-lane and two-way highways have speed/delay as the measure of effectiveness.
3. What is a basic freeway segment?
a) The section between two ramps which is unaffected by weaving and diverging maneuvers
b) The section between three ramps which is unaffected by weaving and diverging maneuvers
c) The section between two ramps which is affected by weaving and diverging maneuvers
d) The section between three ramps which is affected by weaving and diverging maneuvers
Answer: a
Clarification: Basic freeway segment is the section between two ramps which is unaffected by weaving and diverging maneuvers. The ramps are either entrance or exit. In a basic freeway, the traffic flow is steady.
4. In how many steps is the freeway capacity determined?
a) 1
b) 2
c) 3
d) 4
Answer: c
Clarification: The freeway capacity determined in 3 steps and they are theoretical capacity, prevailing capacity, and level of service and design service rate.
5. Basic or theoretical capacity under ideal traffic and environmental conditions can be determined by the concept that the _____
a) flow rate equals time divided by time headway; time headway equals distance divided by speed
b) flow rate equals time multiplied to time headway; time headway equals distance divided by speed
c) flow rate equals time multiplied to time headway; time headway equals distance multiplied to speed
d) flow rate equals time added to time headway; time headway equals distance divided by speed
Answer: a
Clarification: Basic or theoretical capacity under ideal traffic and environmental conditions can be determined by the concept that the flow rate equals time divided by time headway; time headway equals distance divided by speed.
6. How is basic capacity determined by prevailing capacity?
a) Repeated observation of maximum traffic flow under peak conditions
b) Repeated observation of minimum traffic flow under peak conditions
c) Repeated observation of minimum traffic flow under ideal conditions
d) Repeated observation of maximum traffic flow under ideal conditions
Answer: d
Clarification: The basic capacity is determined by prevailing capacity by repeated observation of maximum traffic flow under ideal traffic and environmental conditions. The capacity of a segment of freeway working under no ideal conditions will have capacity less than the basic capacity.