Originally Posted By: paul
so the acceleration from 40 m/s to 67 m/s
in 1 second was 27 m/s/s


Huh? Where does a mass have a velocity of 40m/s? How did it get into that state?

The animation app showed one changing from -40m/s to 69m/s (or similar).

-40m/s is not the same as 40m/s.