A baseball is formed by winding yarn around a small sphere of cork.
The ball is then covered with
two interlocking pieces of white cowhide, which are tightly stitched together.
The mass and circumference of a regulation baseball are
5oz and 9in (i.e., about
and
), respectively.
In the major leagues, the ball is pitched a distance of 60
feet 6 inches (i.e.,
m), towards the hitter, at speeds
which typically lie in the range 60 to 100 mph (i.e., about 30 to 45
). As is well-known to baseball fans,
there are a surprising variety of different pitches. ``Sliders'' deviate
sideways through the air. ``Curveballs'' deviate sideways,
but also dip unusually rapidly. Conversely, ``fastballs'' dip unusually slowly.
Finally, the mysterious ``knuckleball'' can
weave from side to side as it moves towards the hitter. How is all this
bizarre behaviour possible? Let us investigate.