How to Caculate Speed
- 1). Measure off the distance that you will use to calculate the speed of the object. Mark the start and end points clearly. Remember that you will be calculating the average speed over that distance, and that the speed at any particular point may differ as the object you are measuring either speeds up (going downhill, for example), or slows down.
- 2). Start your stopwatch when the object passes the start point, and stop it when it reaches the end point.
- 3). Divide the distance of your measured course by the amount of time on the stopwatch. For example, if your object traveled 200 feet in 80 seconds, its speed was 2.5 feet per second.
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