In 1872, baseball changed forever. Up until that year, baseball gear was a mess. The authorities then standardized the most basic elements. baseball. From then on, every ball was the same. It weighs only 5 ounces. That’s 142 grams. Its circumference is a solid 9 inches. Twenty-three centimeters.
It’s not just the end product. The manufacturing process is highly regulated. Let’s start with the core. a pressed cork Wrap it in black rubber. Add another layer of red gum. Now comes the thread. The wool has three windings of cotton yarn Rubber glue holds the thread in place. Finally, we have a two-piece cover. Sewn with 216 red waxed cotton thread
This is not just a trivial matter. Construction affects everything. Imagine you are playing tennis. The size is also similar. However, tennis balls bounce much better. In baseball, this is called “coefficient of restitution…” Before 1911, cork-centered balls came into play. Home runs are harder to hit. The ball bounces less.
To understand why, we need to look at physics. The researchers used high-speed cameras to analyze the falling balls. This is what happened.
How a Baseball Bounces: The Science of Pitching
Gravity pulls the ball down. All potential energy is converted into kinetic energy of restitution.. Mass is important. Drop height is important.
It stops when the ball hits the floor. For an instant. The kinetic energy becomes zero.
Energy does not disappear. The shape changes. The ball is squeezed. It changes from a perfect sphere to a slightly oval shape. At the molecular level, the long polymer chains inside the core stretch and contract.
The stretch takes less than 0.001 seconds. Then the polymer bounces back. The ball starts to move upwards. Physicists describe this as kinetic energy, which is converted to elastic energy and then back to kinetic energy of restitution..
Part of the energy is lost as heat during compression. The ball never returns to its original height. A baseball can only bounce about 32 percent of its fall.
How does MLB control ball bounces?
Major League Baseball controls the bounce with great care. Once the balls are manufactured, they are taken to the testing facility. They were fired from cannons. Velocity is 85 feet per second. 26 meters per second. They hit the wood surface eight meters away. Twenty-four meters.
The authorities measured the speed of the bounce. They divide it by incident speed. The result should be 54.6%. Plus or minus 3.2%. The return speed should be about 46 feet per second.
The ball must also keep its shape. Withstands 65 pounds of force. The compression set must be less than 0.08 inches. Zero point 2 cm.
Why is this important? Because this object is defined by consistency. If the bounce changes, so does the game. The 5 oz baseball is a well-designed object. Its behavior is predictable. This is what makes baseball a sport of skill. And physics.
