This has got to be known already, but I “discovered” this, never heard it:
To get an athletes speed in MPH, take the Meters/sec time, double it, and add 10%, just like the kilo to pounds conversion. It’s close enough as doesn’t make a real difference:
12.1 M/s=
39.56 Ft/s=
142441 Ft/hr=
26.97 MPH
Or:
12.1 M/s X 2 = 24.2 +10% = 26.6MPH
or
1 m/s = 3.6 km/h (1 m/s x 1 h = 3600 m/1h)
1.609 km = 1 mile so 1 km = 0.6215 M
so 1 m/s = 3.6 km/h = 2.2374 M/h
so
12,1 m/s = 43.56 km/h (= 12.1 x 3.6)
43.56 km/h = 27.07 M/h (= 43.56/1.609)
or directly
12.1 m/s = 27.07 M/h (= 12.1 x 2.2374)
Whatever. I knew my numbers weren’t engineer-accurate but my point was that the formula gets you so close it doesn’t really matter.
yes 2,2 = 2 + 0.2 and 0,2 = 10% of 2…
The problem is that you have to know the 2.2