There are two main areas in the game of baseball where physics play a major role: pitching and hitting. When a pitcher pitches a baseball, it must travel sixty feet and six inches to reach home plate.  As a former pitcher, the importance of a focused windup was always preached to me.  When a pitcher goes into his wind up he attempts to use his body to its best ability in order to provide a high amount of energy to the ball.  A fundamentally sound wind up requires a pitcher to produce a motion that involves the biomechanical principal known as “sequential summation of movement”. (1) This principal suggests that the largest body masses must move first, followed by the smaller ones. (2) In a pitcher’s wind up, his first move is to step back, creating a weight shift through his legs.  He then rotates his hips, lifts his legs, and thrusts his body forward.  The pitcher pointing his shoulder, pumping his arms and flicking his wrist follows up the use of his larger body masses.  How hard a pitch is thrown is most greatly effected by the power generated in the pitcher’s legs and his use of proper arm trajectory.

Hitting a small round ball thrown at a high velocity with the “sweet spot” of a round bat is widely regarded as the toughest thing to accomplish in all of sports.  The sweet spot on a bat is typically about 6.5 inches from the end of the bat.  If a hitter is going up against a 90 mph fastball, impact is set to occur about 400 milliseconds after the pitcher releases the ball.  By making contact as little as 7 milliseconds too early or too late a batter’s swing will result in a foul ball.  In the 400 milliseconds between release and contact, a hitter must see the pitch, judge it’s speed and location, and decide where they must swing in order to make contact on the sweet spot.  Hitting the ball on the sweet spot makes the vibration caused by the ball hitting the bat cancel out.  Since less energy is used on that vibration, more energy can go to the ball. (3) As I know all too well, when a hitter swings and misses the sweet spot, it can result in a vibration that stings his hands and forearms.  At the point of impact (when the hitter’s bat makes contact with the ball) thousands of pounds of force cause the baseball to compress to roughly half of its original diameter.  This causes the ball to bounce off of the hitters bat at dangerously high velocities.

1) http://www.exploratorium.edu/baseball/putting_something.html

2) http://www.physics.usyd.edu.au/~cross/baseball.html

3)http://science.discovery.com/video-topics/sports/the-physics-of-baseball.htm