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rotation, that energy is transferred into linear energy, meaning the last few bounces are higher. A spiral throw has angular momentum, meaning once it starts spinning, it will stay in that same orientation unless another force, like a defensive player tipping the ball, acts on it. The shape of the football means that it will travel aerodynamically, and unless the ball is tipped or another force acts on it, the air resistance forces are consistent. This means the ball holds a constant orientation, so it is much easier for both the quarterback and the receiver to predict the flight path for accurate throwing and catching. By comparison, a ball thrown end over end does not have angular momentum and is constantly changing shape as it tumbles through the air, so the air resistance forces are constantly changing as well. Non-spiral passes appear to flutter around in the air, right? These passes usually end up in a very

The linear kinetic energy in a thrown ball determines how high or far it will go.

16 CONNECTING STEM AND SPORTS | FOOTBALL