Sargent-Welch Physics of Baseball Activities
This set of activities explores some of the fundamental physics behind the grand old game. They involve equipment available from
. They are all pdf files. Please enjoy them and feel free to send feedback to me at the address below.
The Physics of a of a Baseball in Flight
- Flight of Fancy - COMING SOON!
- In the "Fall Classic" experiment, you learned about gravity and how it effects objects that are falling straight downward. Here you will understand how gravity affects a flying object like a lined shot headed for the Green Monster.
- The Best Launch Angle
- If you want to hit a homerun, you certainly want to hit the ball as hard as possible, but what angle should you launch it for the greatest distance? Do you think the best launch angle for the baseball is 45-degrees? Is it more or less?
The Physics of a Baseball Bat
- The Center of Mass
- Why do some bats feel right and others not so much? There are several design features of a baseball bat in addition to its mass and length. They are the location of the center of mass (CM), the moment of inertia (MOI), and the vibrational nodes (VN). All of these determine the feel and effectiveness of a bat. After this activity, you will understand the center of mass (CM) and how to find it for several objects including a bat.
- The Concept of Rotational Inertia
- Rotational inertia is the resistance an object offers to changes in its rotational motion. It depends upon the mass of the object and the way the mass is distributed.
- Calculating the Moment of Inertia
- You will get to understand more about the idea of rotational inertia by learning how to measure the "moment of inertia (MOI)." The MOI is a numerical measure of the rotational inertia. You will measure the MOI of a meter stick and a baseball bat.
- Vibrational Nodes
- Have you ever hit a ball off the end of the bat and felt the "hand full of bumble bees?" When a bat hits the ball, the bat can start to vibrate. When this happens energy that could go into making the ball go further is used to make the bat vibrate. Part of designing a good bat is to be sure that the part of the bat that is likely to hit the ball should result in as little vibration in the bat as possible. You'll investigate the nature of these vibrations.
The Physics of Hitting
- The Coefficient of Restitution
- The rules of baseball state a legal baseball traveling at 60mph at a wall of northern white ash must rebound with a speed of 54.6% +/- 3.2% of the initial speed. This number, 0.546, is called the "coefficient of restitution" or COR. You will measure the COR of a several balls including a baseball.
- COR and Temperature
- The COR of a baseball is supposed to be precisely 0.546. However, this value depends not only on the properties of the ball, but also on the temperature and humidity of the ball. This experiment will illustrate the effect of temperature on the COR.
- Bat Performance Factor
- The COR of a baseball slammed against a wall is about 54.6%. Is it the same for a ball hitting a bat? Well, that depends upon the bat. The Bat Performance Factor or BFP is listed on most aluminum bats you buy. You will understand why the rules of many leagues only allow bats with a BFP of 1.20 or less.
