A truck covers 40.0 m in 7.65 s while smoothly slowing down to final speed 3.40 m/s. whats the original speed and what is its acceleration?? The initail position is 0, the final position is 40. THe initial velocity we don't know, the final velocity is 3.40 m/s. The time it takes is 7.65 and the acceleration we don't know. Do I have that right? and when I set it up in the formulas there are two unknowns and I work it out and it never comes out to be the right answer.