1. The problem statement, all variables and given/known data A car, initially going eastward, rounds a 90 degree bend and ends up heading southward. If the speedometer reading remains constant, what is the direction of a car's average acceleration vector? -So i know the speed remains constant. 2. Relevant equations average acceleration =( final velocity - initial velocity ) / elapsed time 3. The attempt at a solution initial velocity = vi + 0j final velocity = 0i + -vj average acceleration = (-vi + -vj) / elapsed time I don't think that the time matters here, because the ratio of vj/vi will remain the same, so: direction of motion = inverse tangent of (-vj/-vi) = 45 degrees. I feel like the answer should be -45 degrees. Also the back of the book says average acceleration = 5.12 m/s2 and that the angle should be 41 degrees south of west. How can they get an actual value for average acceleration? Any help would be greatly appreciated.