First time I wanted to know how tachymeters worked was like 4 years ago, but I finally figured out the tachymeter from watching this. Other videos I watched 4 years ago were impossible. Thank you so much!
It's easier if you're just talking about completing 1 unit rather than 200M. Say you start timing a racecar, and you stop it exactly when it has gone 1 mile. Whatever number on the tachymeter the second hand is pointing to is how many miles per hour the car was going.
This video from Watchbox Is the best I have ever seen on the Navitimer slide rule bezel. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-lmdm3DyVSy4.html
A seemingly useless scale. With tacymeter, if I measure the time it takes a car to travel 1/2 mile track, and the tacymeter scale says 120, then the car would do 120*.5 miles an hour or 60 MPH. If instead I measured that the car did 1/2 mile in 30 seconds, then (.5/30) mile/second. To convert miles/second to mph, we just multiply by 3600. .5/30*3600=60 MPH. I suppose some people might prefer the reduced math using the tachymeter. I can't dispute that, but I found it more intuitive to think of the math, and I didn't do it the hard way. I just realized that 60 MPH is a mile per minute, and if I did a 1/2 mile in a 1/2 minute, that's the same speed.
Very well said! On the other hand, life experience has shown me that mathematics and other things involving critical thinking tend to be things that many avoid whenever possible.
