The Race

Runners travel at varying speeds during a race. Average speed can be determined by dividing the total distance by the total time. Graphically, average speed is the slope of a line drawn between the initial and final points of the graph. The graph below shows an actual motion and the graph of its average speed.

Graph

1. Imagine that each runner could actually run at a constant speed and that you are watching the race from a stationary point. Use this applet to view the results. Launch Applet
2. Calculate the average speeds of the runners in Lanes 1, 2, and 3 in the applet. Which runner has the fastest average speed?

Why this problem?
This problem will:
blue check provide both a visual and a graphical comparison of actual speed and average speed over an entire race;
blue check relate a visual image of a race with its graphical representation;
blue check provide practice in extracting data from a graph in order to calculate speed;
blue check provide practice in using a graph to determine changes in speed.

Printable PDF Check Answers

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