4.7 DistanceTime Diagrams
A distancetime diagram is a linear diagram which shows the correlation between distance and time. One usual example is the diagram which shows how one or more people move during a certain time.
If Fredrik cycles with a constant speed between point A and B, the diagram should look like this.


In this diagram, we also see Ingela who is cycling faster than Fredrik and arrives at point B more quickly. She then stands still and waits for Fredrik. That she is standing still, we can see by looking at the value on the yaxis. The distance doesn’t change while at the same time, the value of the xaxis, time, does change.


Now there is Noah in the diagram. We can see that he first cycles slowly. He begins then to cycle more quickly and reaches point B at the same time as Fredrik. When the line’s slope is steeper, this means that the change in the yaxis increase in correlation to the change on the xaxis. This means that the person covers a longer stretch during a shorter time. 

Below are five different stories:
1 
Per downhill skis down a slalom slope and goes faster and faster the whole time. Finally, Per stops because it is too fast.



A

2 
Alice is cycling to football practice. When she has cycled a bit, she remembers that she has forgotten her mobile telephone and turns around to go home. She is running short on time, so Alice cycles faster than usual to practice.



B 
3 
Erik is out running. He is doing interval training and this means that he runs a stretch, rests, runs again and so forth. 


C 
4 
Eva is driving her car to work. It is motorway almost the whole way and she can drive 110 km/h. A few times, she needs to slow down to 70 km/h. 


D 
5 
Nils is sick today and spends all day in bed playing Xbox360. 


E 
