A car that was initially at rest reaches a final speed of +50.0 m/s over a displacement of +55.0 m.

What is the magnitude of the acceleration?

Find the time it took to travel the first 55 m.

2 answers

a=v²/2s=...
s=at²/2 =>
t=sqrt{2s/a)=...
I don't understand.. could you give a better answer?