Physics and baseball

1. Physics and baseball Marlin Connelly

2. Introduction Out of all sports, baseball is probably the one that is most affected by physics. On a single play, there is so much going on that relates to physics. From the work a pitcher does on a ball, to the collision between the bat and the ball, to the path a ball takes through the air, physics has a huge impact on a baseball game.

3. Pitchers The key concept of a pitch is how it interacts with the air around it. A pitcher first winds up, and does work on the ball by transferring energy to it. This gives the ball a velocity as it is released into the air. Depending on the spin of a ball, it can dip, dive, or cut to a side. The ball interacts with both gravity and frictional forces in the air to determine where it will fall. Because of spin, air will flow faster on one side of the ball than the other. And according to Newton’s third law, for every action force there is an equal and opposite reaction force. So while the ball is acting on the air, the air is also acting on the ball, which will determine where it falls, and which direction it will move. This reaction force is known as a Magnus Force. Take a fastball, for example. A fastball is thrown with backspin, so the Magnus Force is aimed upwards, opposing gravity. This gives the illusion that the ball is moving upward. While it is impossible for a pitch to move upward because of just a Magnus Force, it does fall at a slower rate, which can confuse the batter.

4. Batters While standing at the plate, a batter has many responsibilities. First, he must determine the speed and spin of the ball to locate when and where he should make contact with it. Then he must swing and make contact with the ball, which will determine its path in the air. There are many factors to consider once a ball makes contact with the bat. The first thing of note is the mass of the bat. The heavier a bat is, the more momentum it will transfer into the ball, which will give the it a larger velocity as it flies through the air. However, it is harder to generate a high velocity with a heavier bat, so a batter must use a bat that is of just the right mass, which can optimize the momentum transferred to the ball. The other factor to consider is where the bat makes contact with the ball. The goal of a batter is to make contact at the “sweet spot”- the spot on the bat that will transfer the most energy to the ball. Where the ball makes contact with the bat will control the speed and spin of the ball as it flies through the air. This, in turn, will affect the effects of gravity and the Magnus Force, which will determine where the ball will go.

5. Works Cited • Nathan, Alan M. "The Physics of Baseball." Help.physics.uiuc.edu. University of Illinois. Web. 02 Dec. 2011. <http://webusers.npl.illinois.edu/~a-nathan/pob//index.html>. • Russell, Daniel A. "What(and Where) Is the Sweet Spot of a Baseball/Softball Bat?" Kettering University - 1700 University Avenue - Flint, Michigan 48504-6214. Web. 02 Dec. 2011. <http://www.kettering.edu/physics/drussell/bats-new/sweetspot.html>. • Solomon, Christopher. "The Physics of Cheating in Baseball | Science & Nature | Smithsonian Magazine." History, Travel, Arts, Science, People, Places | Smithsonian Magazine. Web. 02 Dec. 2011. <http://www.smithsonianmag.com/science-nature/The-Physics-of-Cheating-in-Baseball.html?c=y>.