This is the perfect and most accurate way to caculate speed (can u beleive a 12 yr old told me this he must of learned it in science or something) I tried it and it works. Measure a distance of a street up to 200 ft or more.Mark a start and finish line.Make sure you get a good running start before you hit the starting line, to have your pb at top speed. Have someone time how long it takes you to get from start to finish line (with a stopwatch).Say it took 3.7 seconds this means you were going 200 feet / 3.7 seconds = 54 ft per second. so then you find out how many mph it is. So if theres 3600 sec in a hour you were doing about (54ft/sec x 3600 sec/hour) = 194,400 feet in 1 hour. If their are 5,280 feet in a mile then (194,400 / 5280) = 36.8 mph. See easy as that the general formula for finding mph from feet per second is fps x .682 = mph
Perfect way to caculate speed 
