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QuesTec is a digital media company known mostly for its Umpire Information System (UIS) which is used by Major League Baseball for the purpose of providing feedback and evaluation of Major League umpires. The QuesTec company, based out of Deer Park, New York, has been mostly involved in television replay and graphics throughout its history. In 2001, however, the company signed a 5-year contract with Major League Baseball to use its pitch tracking technology as a means to review the performance of home plate umpires during baseball games. The contract has continued through the 2008 season by annual extension and topped out at 11 ballparks. In 2009 it was replaced by MLB's Zone Evaluation.

This is an interesting question. A more generic question is whether there is some substance that is compressible (so as to store energy) but not so compressible that it does not return the energy to the ball. This is a question that is worth thinking hard about and worth doing some experimental measurements to study the effect. Such experiments are currently in the planning stage.

The trampoline effect is quite well known in hollow metal bats. The thin metal shell actually compresses during the collision with the ball and springs back, much like a trampoline, resulting in much less loss of energy (and therefore a higher batted ball speed) than would be the case if the ball hit a completely rigid surface. The loss of energy that I referred to comes mostly from the ball. During the collision, the ball compresses much like a spring. The initial energy of motion (kinetic energy) gets converted to compressional energy (potential energy) that is stored up in the spring. The spring then expands back out again, pushing against the bat, and converting the compressional energy back into kinetic energy. This is a very inefficient process in that only about 25% of the stored compressional energy is returned to the ball in the form of kinetic energy.

The efficiency of the bat in transferring energy to the ball in part depends on the weight of the part of the bat near the impact point of the ball. For a given bat speed, a heavier bat will produce a higher hit ball speed than a lighter bat. That is why the head of a golf driver is heavier than that of an iron: you want to drive the ball further. By reducing the weight at the barrel end of the bat, the efficiency of the bat is reduced, giving rise to a reduced hit ball speed and less distance on a long fly ball. This is the downside of using a corked bat.

The natural frequency of wooden bats is around 250 cycles per second, or 250 Hertz. Because the ball leaves the bat so soon (1 millisecond), the energy transfer to the ball is not too efficient. If the bat has been hollowed and corked, it's no longer as stiff and it will get an even lower natural frequency and an even less efficient transfer of energy to the bat. The baseball bounces off the bat faster than the cork can store the energy that could be put back in the ball. The cork might deaden the sound of a hollowed out bat, but it doesn't propel the ball. It can't. So, balls hit with corked bats don't go as far.

A baseball bat has three "sweet spots"; one of them is called its "center of percussion" (COP). That's physicist talk for the point where the ball's impact causes the smallest shock to your hands. If you hit a baseball closer to the bat's handle than to the center of percussion, you'll feel a slight force pushing the handle back into the palm of your top hand. If you hit the ball farther out than the COP, you'll feel a slight push on your fingers in the opposite direction, trying to open up your grip. But if you hit the ball right on the COP, you won't feel any force on the handle. To find the COP on a bat, try this simple activity.

The secret to understanding a curveball is the speed of the air moving past the ball's surface. A curve has topspin, meaning that the top of the ball is moving in the same direction as the throw and the OPPOSITE direction of air flow relative to the direction of the throw. Vice versa for the bottom of the ball. It moves in the SAME direction as the air flow relative to the throw. See Bernoulli's principle, which says that the lower velocity of the air over the ball creates more pressure on the ball, which is what makes the curveball break downward. (Thanks to Lizbeth for correcting this info)

For over a century baseball fans have debated the question of whether a "curve ball does in fact curve". Only rarely has there been objective scientific testing in order to verify what is so obviously the appearance of a curve.

Igor Sikorsky's interest had stemmed from a phone call he received from United Aircraft's Lauren (Deac) Lyman who over lunch with Walter Neff of United Airlines, had discussed the question of the trajectory of a baseball.

Mr. Sikorsky, who has a wind tunnel, called his engineers together presenting the problem as follows: "Here we have a solid sphere, moving rapidly in space and rotating on a vertical axis. You see? ... the object is to elude the man with the stick". It should be noted that baseball was a rather foreign endeavor to Mr. Sikorsky.

To hit a ball the maximum possible distance, the trajectory off the bat should have a 35-degree angle.

A line drive travels 100 yards in 4 seconds. A fly to the outfield travels 98 yards in 4.3 seconds.

An average head wind (10 mph) can turn a 400-foot home run into a 370-foot routine out.