LESSON 4 Distance vs. Time

1. If you walk at a steady pace for one hour, how far can you walk?
2. If you walk at a steady pace, how long does it take you to walk a mile?
3. What can you measure that will help you answer these questions?

To find out how fast someone or something is moving, we measure speed. To measure speed, consider both time and distance. Speed is the ratio of distance to time. So, speed can be written as a fraction:

Since speed involves both distance and time, the unit of measure involves both as well. Speed is measured in miles per hour, meters per second, or feet per second, and so on. For example, if a car travels 55 miles in one hour, the speed of the car is or 55 mph. If a toy car travels 6 meters in 2 seconds, the speed of the toy car is , which is equivalent to .

 

 

In this experiment, you will measure the time it takes one of your classmates to walk three different distances so that you can find his or her walking speed. One way to do the experiment is described here. Your class may need to use a different setup.