Question

Explain the importance of the seams on a baseball when pitching a curveball. What would you change in the design of a baseball for high altitude locations like Denver so that it would play similarly to a standard baseball in New York.

Answer 1

When we throw a baseball, a lot of things have a large effect on the motion of a baseball as it is traveling, but the most important ones are the release point and the grip. Why the grip is so important is because the baseball has raised seams. When the ball is traveling through the air it is rotating. Since there is air resistance the seams play a key role in the motion of the baseball. The seams in conjunction with the rotation can cause the ball to maneuver in the air. As the ball is traveling through the air it is creating high and low-pressure fronts(magnus effect). The seams can cause turbulence in the motion.

The reason why grip has a lot to do with the motion of the baseball is it largely determines the rotation of the baseball. The rotation of the baseball in combination with the way the seam is spinning through the air causes the ball to move in different patterns.  A few common pitches are the fastball, curveball, slider, and the screwball. Each of these pitches has a different spin because of how the player grips the ball.

A curveball is thrown with topspin that creates a higher pressure zone on top of the ball (magnus effect), which deflects the ball downward in flight. Instead of counteracting gravity, the curveball adds additional downward force, thereby gives the ball an exaggerated drop in flight.

At high altitude, the air pressure is lesser and hence, the net force due to the magnus effect is also lesser. For a curveball delivered at denver to dip more, it should be made heavier in comparison to a ball that is being delivered in new york.