posted by Johnny .
When I toss a ball straight up, it travels up, stops, and then falls back to by hand. When it stops to change direction, how long is it stopped?
The veloicty is linear
As an example
V=10- 10t so at t=1, velocity is zero. Is it zero at .999999999999 or 1.0000000001 sec? No.
What does that tell me? Just as a point in space has no dimension while a line does, is there a period of time that has no "length",ie ifinantely short?