If a ball is launched into the air vertically with a velocity of 20 m/sec, how fast will it be moving after two seconds? (The gravity's acceleration is rounded to 10 m/sec/sec.)
vf=vi+gt
=20-9.8*2 m/s If you round to ten, vf is zero.
Why do folks use 10m/s^2 as g? Nowhere on the Earth is it that value. Why not use 3.0 as PI?