Posted by Emma on .
4. An automobile is traveling at 30 km/hr. It accelerates at 3 m/s2 until it has covered 100 meters.. What is its new velocity?
I asked my teacher on what formula I should use and said I should use this one: V^2= Vo^2+2ax (V^2 is the velocit, Vo is the initial velocity, a is accerlation and x distance
I used that formuala and got 668.90 m/s
V^2= (8.3 m/s)^2+2(3m/s^2)(100 m)=668.90 m/s
I converted 30km/hr by doing this:
(30 km/hr)(1000 m/km)(1hr/3600)=8.3m/s
That answer my teacher said I was suppose to get is 25.9 m/s and that I could convert it to 93.2 km/hr.

Physics Word Problem 
DrBob222,
Your 668.90 is for V^2. Take the square root of that to get 25.9. You just omitted a step.