The Animated Chaotic Pendulum

• "reload" to make it swing
• From student's homework on Web
• Newton's angular laws of motion
• Periodic driving force, viscous damping, nonlinear (sinA) restoring force:

  

  The angular displacement of the pendulum versus time. The red vertical line shows the current angular position of the pendulum.

  

  A phase space plot (angular velocity versus angular displacement). The red vertical line shows the current position and velocity of the pendulum.