posted by Delilah .
A baseball player hits a line drive. Just before the ball is struck, it is moving east at a speed of 43.2 m/s (97 mi/h). Just after contact with the bat, 9.30 10-4 s later, the ball is moving west at a speed of 52 m/s (116 mi/h). Find the ball's average acceleration.
Calulate the VECTOR velocity change and divide it by the time interval. Since the direction changes by 180 degrees, the velocity change is the sum of the before and after speeds.