When you hit the volleyball just right, you can make it spin as it moves through the air. A spinning volleyball develops a boundary of air that sticks to the ball as it travels. The boundary air on one side of the volleyball collides with air moving in the opposite direction, causing an area of high pressure. The spinning boundary air on the opposite side of the volleyball moves in the same direction as the air. Since the boundary air is moving in the same direction as the rest of the air, there is no collision and the air rushes over the volleyball quickly, setting up an area of low pressure. The volleyball naturally wants to follow the path of least resistance, turning away from the high pressure toward the low pressure.
Topspin
An athlete can apply the Magnus effect in any direction to create backspin, topspin and sidespin on the volleyball. A volleyball player will apply topspin to the ball, causing the volleyball to spin forward as it moves through the air. Topspin works with gravity to cause a downward pull so that the volleyball arcs over the net and then drops suddenly. Adding topspin to the volleyball causes it to accelerate once it hits a surface, surprising the opposing team member attempting to return the ball.
Backspin, Left and Right
Use the Magnus effect to slow the volleyball or make it turn left or right. Applying a backspin on the volleyball causes the ball to rotate backward as it flies through the air. Backspin works against gravity to make the ball move slowly, or hang in the air. Backspin decelerates the volleyball, making it difficult for the opposing team to return the ball with any kinetic energy. Adding sidespin makes the volleyball turn left or right as it moves through the air, and combining sidespin with topspin or backspin makes the volleyball fly in unpredictable ways.
Amount of Spin
The amount of spin is as important as spin direction. Serve the volleyball with very little spin to make it float above the opposing team. The ball will shift and flutter as it flies through the air, making it very difficult to predict where the volleyball will land and how it will behave upon the return. Add a lot of spin to make the volleyball accelerate through the air.
