Friday, 12 August 2011

Since I got this GUESS watch from Milton around November 2008 (didn't realise I've been wearing this watch for almost 3 years already!), I never bother to go find out what this TACHYMETER is. If you do not know, it is the name of this scale inscribed at the surrounding rim of some of the analog watches You can have a look at my watch here:

So.. I went to google it and clicked to see what Wikipedia has to say! and it says...

"A tachymeter is the name of the scale sometimes inscribed around the rim of an analog watch. It can be used to compute speed based on travel time or measure distance based on speed. The function performed by a tachymeter is independent of the unit of distance (e.g. statute miles, nautical miles, kilometres, metres etc.) as long as the same unit of length is used for all calculations. It can also be used to measure an industrial production process in units per hour. A tachymeter is simply a means of converting elapsed time in seconds per unit to units per hour.
For example, say you measured a speeding plane over the distance of 1 mile. You start the clock as it crosses the "starting line" and stop the clock as it passes the 1 mile mark. If the plane is traveling at an average speed of 400 mph, we would expect it to travel 1 mile in 9 seconds. If this were the case, you would stop your watch at 9 seconds, which corresponds to the 400 unit mark on the tachymeter. Had we wanted to use kilometers, we would simply stop the clock at 1 kilometer and if the plane took 9 seconds to travel 1 kilometer, clock the average speed at 400 km/h. Smaller fractional units can be used for slower objects, like runners, turtles and snails, but the same X/hour function remains constant."

... which sounds very confusing to me because I don't know what the heck all this babbling is about. So, for an easier solution, I opt to search for a video which can explain to me what it is! Sounds like a much better idea, huh? and indeed, my problem is solved with just one video! The explanation is really good and easy to understand! Have a look for yourself;
So basically, what is it for and how does it works? From my understanding, it is used to measure how fast a vehicle moves (miles per hour)! Time your vehicle by preparing a 1 mile track. Start time when the vehicle leaves from the starting line and mark your tachymeter at the point that the second needle is pointing. If it is pointing at 45 seconds and 80 on the tachymeter scale, it means that the vehicle is moving at 80 miles an hour! So simple, right?!

Another knowledge gained on a random curious thought day!




  1. i never knew photography could be so deep...

  2. Yea. Photography is actually more than what I have perceived it as. Photography talks are pretty interesting ;)