A line drive goes over first base in fair territory but lands on the foul side of the first base line. Is that ball fair or foul?
In this scenerio the ball is foul. Since the ball was in flight while it crossed over the base but then landed in foul territory it is a foul ball. If this was a bounding ball (one that hit the ground before the base) and bounced over the bag and then went foul it would be a fair ball because any bounding ball over a base is considered a fair ball. This is typically the base umpire's call but in the two umpire system I sometimes like to have the plate umpire call it because he is in a better possition and usually has a better angle.