Why Tennis Balls Bounce

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The design of a tennis ball results in aeronautics and helps you play a better tennis game. The balls often fly through the air and bounce high off the ground. The mobile ball bounces for many reasons. These reasons include kinetic energy, shape, materials and the gas manipulated into the ball.

Kinetic Energy

The motion of energy defines kinetic energy. According to Exploratorium, when you throw a tennis ball and it lands on the floor, it gains kinetic energy. The molecules in the tennis ball begin to stretch apart. Then, they squeeze back together. As this process occurs, the ball gains more energy and is able to bounce off the ground.


As a tennis ball gains kinetic energy, it transforms shape from oval to round sights Exploratorium. With the transformation, the molecules cause the tennis ball to bounce up. The ball bounces because it must transform itself back into the round shape.


Rubber balls contain more bounce than other types. Rubber consists of a strand of polymer molecules, cites Exploratorium. These molecules form a mass of molecular structure that entwines itself. When a tennis ball is thrown to the floor, the molecules unwind for an instant. Then, the rubber condenses them back together causing upward motion to occur. This results in a bounce. Furthermore, the fuzz on the outside of the tennis ball plays a role in its ability to bounce. According to the National Aeronautics and Space Administration, the fuzz adds additional friction and increases the bounce velocity.

Air Inside Ball

Most tennis balls contain gas inside them, cites The K-8 Aeronautics Internet Textbook. The air or gas inside the tennis ball expands when the ball is thrown onto the ground. As the expansion occurs, the ball gains more momentum, allowing it to bounce off the ground. The gas strengthens the kinetic energy, resulting in a bouncing ball.