Tachymeter Explained! (5 examples)

This video aims at clarifying the tachymeter function found on some watches. Hope it helps! :)

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A tachymeter (also spelled as "tachymetre") is a function on a watch primarily used for measuring speed; however, it can be used to compute many other things as well.
The tachymeter scale is usually inscribed around the bezel or the outer dial of the watch. Mathematically, the Tachymeter Dial = 3600 divided by the Elapsed Time In Seconds.
As a result and due to accuracy and practical reasons, the printed tachymeter scale is valid for all times up to one minute from approximately 7 seconds.
Moving on to some examples.
Example 1: Let’s say you are watching a racing event and you want to determine the speed of a car. In the race magazine, you read that the distance between Curve A and Curve B is exactly 1km. Using your chronograph, you notice it takes the racecar 20 seconds to cover this distance. The tachymeter scale reads 180. This means that the average speed of the car was 180 kilometers per hour. Keep in mind; you can use other units of measurement. For example,
Example 2: The race magazine also tells you there is a distance of 1 mile between Curve A and Curve C. Repeating the exercise, it takes the car 35 seconds to cover this distance. The tachymeter scale now indicates slightly above 100, meaning the car’s average speed was just above 100 miles per hour.
Example 3: Another example, let’s say we want to measure how fast Usain Bolt runs 200 meters in the Olympics. Using the chronograph, we notice it takes him 20 seconds to complete the race. The tachymeter scale indicates 180 km/h; however, we have to be careful and remember the race was only one fifth of a kilometer, so we need to get one fifth of 180 which equals the actual average speed of the runner; 36 km/per hour.
Example 4: Another example, let’s say you visit a car factory that completes one car every 45 seconds. Reading from the tachymeter, you conclude the factory on average completes 80 cars per hour.
Example 5: Now let’s say you’re visiting a luxury watch manufacturer. Observing the assembly line, you notice the manufacturer produces one watch every 100 seconds. You can still use the tachymeter scale even if this time is above 60 seconds. In other words, if the manufacturer produces one watch every 100 seconds, this is the same as half a watch per 50 seconds. 50 seconds is within the valid range of the tachymeter scale and as a result, you can calculate that 72 half watches (or 36 whole watches) are completed on average in one hour.
If you enjoyed this video, visit my channel to see other explanation videos and watch reviews including a review of this Omega. Have a good day, bye!