Speed

Everyone knows what speed is but do you know how to measure it?During the last few days, my partners and i have been measuring the speed, calculating it and graphing it. We have a runner in our group and we measure the speed with the distance and the time. 
Table/Chart:

Average Speed
Time (sec)			Distance
		10	20	30
	Trail 1	2.25	2.75	5.06
	Trail 2	2.36	2.99	5.23
	Trail 3	2.06	4.09	6.15
	Average Speed(sec)	2.2	3.3	5.5

Graph:

Speed Calculation: 

There are three different kind of speed. Constant speed is traveling in the same distance each second. Instantaneous speed is speed at a specific instant in time. Average Speed is the total distance traveled divided by the total time it take to travel that distance. So what is the difference between instantaneous speed and average speed? The differences the two speeds are that instantaneous speed travel in an instant while for the average speed you have to find the average of the distance with the time it takes.

For the graph, the lines are not in a straight line. At the starting point, from about 1 to 2 sec the line is a upward curve which indicates that the runner is speeding up. And from about 2 to 5 line is a downward curve which indicates that the runner is slowing down.