Five people per square metre (walking in step)

In the classroom exercises we illustrate the density v flow relationship using a loop of string. The loop has an area of 1 square metre.

When crowds march in step the flow rate can increase. There are a number of environments that this can happen, such as city commuters, marches to music, etc. We illustrate this by asking the group (now at 5 people per square metre) to march in step. You can see the increased flow rate in the video clip above). Movement starts to become constrained if the crowd is either a mixed population or, as you can observe this at any busy rail station, there is one person walking out of step within an ordered crowd. The flow rates drops as shown in the graph below.

Click on the links below for a video clip of: 

2 people per square metre

3 people per square metre

4 people per square metre

5 people per square metre

6 people per square metre

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