A section of an arterial road has been found to have a speed-density relationship that was modelled using the following form:

where v is the space-mean speed in kilometres per hour (km/h), and k is the density in vehicles per kilometres (veh/km).

The relationship was found to have the best fit to the data by using the following coefficients:

a = 3.5

k_m = 126 veh/km

Which is the critical density (ie the density at which the capacity is obtained) of the above arterial road?

The fundamental diagram for a road section can be modelled using a triangular flow-density relationship, having a capacity (maximum flow) of 2000 vehicles per hour (veh/h), a free-flow speed of 80 kilometres per hour (km/h), and a jam density of 125 vehicles per kilometre (veh/km). 

In the peak hour, the congested traffic condition is observed with a speed of 42km/h. What is the density during this peak hour?

A linear regression fit to real traffic data speed (v) and density (k) data has the following relationship: v= 83 –0.5*k, where v is measured in kilometres per hour (km/h) and k is measured in vehicles per kilometre (veh/km). What is the maximum flow of this fundamental diagram?

Round your answers to the nearest 2 decimal points in veh/h. Note: Only include the numerical value (e.g. 51.36)

If only the flow

of vehicles passing by a fixed location on a section of roadway is known then

which of the option(s) below can be determined:

Four vehicles are traveling on a 4-kilometer circular track. The four vehicles are traveling at constant speeds of 46 km/h, 61 km/hr, 62 km/hr, and 70 km/hr, respectively. Assume you are an observer standing at a point on the track for a period of 30 minutes and are recording the instantaneous speed of each vehicle as it crosses your point.  What is the space-mean speed for this stream of traffic?

Round your answers to the nearest 2 decimal points in km/h. Note: Only include the numerical value (e.g. 51.36)

The speeds of six vehicles collected at a fixed location on a long straight road section were 73 km/h, 81 km/h, 61 km/h, 77 km/h, 79 km/h and 79 km/h. What is the space-mean speed for this stream of traffic? 

Round your answers to the nearest 2 decimal points in km/h. Note: Only include the numerical value (e.g. 51.36)

The average headway of traffic on a single lane road has been measured as 8 seconds. What is the flow on the road?

Round your answers to the nearest 2 decimal points in veh/hr. Note: Only include the numerical value (e.g. 51.36)