Omega SPEEDMASTER MOONWATCH - Tachymetric Scales; Understanding Tachymetric Scale Usage; Example: Calculating Vehicle Speed

TACHYMETRIC SCALES
The desired information is read between the central seconds hand of the
chronograph and the corresponding scale, over a maximum duration of 60
seconds.
Example: calculating the speed of a car.
Record the time the car takes to cover a distance of 1 kilometre. Read off the
tachymetric scale the speed indicated by the central seconds hand. In this case,
the car is travelling at 120 km/h.
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