The fastball does what one might expect, which is to simply overpower the batter with sheer speed. Typical fastballs range from 90 mph to 100 mph, although Cincinnati Reds reliever Aroldis Chapman holds the world record fastball of 105 mph. As with any other projectile, fastballs abide by the principles of projectile motion. The fastball’s vertical component of acceleration is ay = -g, while the horizontal component is ax = 0. Thus it is in free fall.

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There are two primary types of fastballs. First is the 4-seam fastball, in which the pitcher releases the ball with backspin such that all four seams “catch air.” Due to the Magnus Effect, this generates enough lift that the ball tends to “float.” This actually refers to an optical illusion that makes it seem to the batter as though the ball is rising, when it is actually falling more slowly than normal. The second fastball is the 2-seamer, where only two seams “catch air.” In this case, less lift is generated, and the ball will drop more quickly.

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For an impressive fastball, click below: www.youtube.com/watch?v=ngubly4hpHw