JCPL Teens

It was believed that a curveball was an optical illusion until 1852 when German Physicist Gustav Magnus demonstrated a spinning object will experience a sideways force.  This principle is called the Magnus Effect. When a ball moves through air it creates a wake which will slow the forward motion of the ball.  With a spin the wake is deflected sideways and as a result the ball is pushed sideways.  The Magnus force is in direct proportion to the rate of spin and speed of the ball.  Faster speeds and faster spin will make a greater curve.  Air density will also affect the curve.  Curve balls at Coors Field in Denver will curve less than those thrown at the lower altitude stadium of Wrigley Field in Chicago. 

Want to know more sports science?  Check out the book Why a Curveball Curves: The Incredible Science of Sports edited by Frank Vizard.