3. Jeff Gordan accelerates his race car at 2.7 m/s2 and covers a distance of 400 m. What is his final velocity at the end of the 400 m distance?

A14 kg rock starting from rest free falls through a distance of 5.0 m with no air resistance. find the momentum change of the rock caused by its fall and the resulting change in the magnitude of earths velocity. earth mass is 6.0 * 10^24 kg. show your work assuming the rock earth system is closed.