small image of a bobblehead doll: Bob Uecker
1. Science of baseball2. Denver's big advantage3. Love that curve ball! 4. Rained out?5. National spot: Mouth cancer

  'talk' balloon coming from Bob, says: 'A Why Files Grand Salami!'

High-flying hits
Baseball atmospherics. Not the aroma of beer spilled on stale popcorn. Not the foghorn-voiced jerk behind you, braying that insightful advice to the blind guy in the umpire's uniform.

We're talking, as nerds would, about the effect of air on the ball. It turns out that air -- the fluid in which a baseball moves -- can slow a ball, change its direction, or both.

Let's get basic for a second. Eventually, any airborne object that's moving slower than escape velocity (about 18,000 miles per hour), will return to Earth. Balls and other objects travel in a horizontal direction only until gravity brings them down to Barry Bonds's mitt, the left-center-field stands, or the infield grass.

After a baseball is hit, three major factors affect how far it travels through the air:

Velocity: The faster the ball's initial speed off the bat, the further it goes (like, no duh?).

Angle: Balls hit too low will return to Earth too soon; balls hit too high will travel a long way vertically, but not horizontally. In the middle is a "sweet spot" where horizontal travel is greatest. (Can you use the Java applet to find the angle that gives the longest distance?)

Air resistance: As a moving ball shoves air aside, it transfers kinetic energy to the air. Since acceleration = force/mass, the ball must decelerate -- slow down. That means the ball can't travel as far in the limited time available before gravity pulls it back to Earth.

As you mess with the applet on this page, notice that Denver's 5,280-foot altitude can add about 35 feet to the longest hit thwacked at the optimum angle and at 130 mph.

Why do curve balls curve?


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