Question

You are observing traffic in a single lane of a highway at a specific location. You measure the average headway and average spacing of passing vehicles as 3 seconds and 150 feet, respectively. Calculate the flow, speed and density of the traffic stream in this lane.

Answer 1

Answers:

1) flow of traffic =
`1198.8 veh/h`

2) average speed =
`34.09 mi/h`

3)density of traffic =
`34.34 veh/mi`

Step-by-step explanation:

1) to find flow of traffic

we use the relation

`q=1/h`

where q is the traffic flow and h is average time headway.

`h= 3s`
`(given)`

insert the value

`q=1/3=0.333veh/s=1198.8veh/h`

2) to find average traffic speed

use the relation

`u=S/h`

where u is average speed S is average spacing and h average time

`S= 150 ft`
`(given)`

so inserting the values

`u= 150/3*3600/5280=34.09 mi/h`

3) density of traffic

`K=q/u`

where K is density of traffic q is flow of traffic and u is average speed

inserting values from above solved parts

`K=1198.8/34.09=34.34 veh/mi`