Simulate and Animate a Foucault Pendulum at the North Pole A Foucault pendulum demonstrates the rotation of the Earth. The pendulum has a long cord and swings in a Newtonian frame since it is mounted on a frictionless hinge. But since we are observing in the Earth (non-Newtonian) frame, we can see the effect of the Earth's rotation in the ground track of the pendulum. Figure 1 File Edit View Insert Tools Desktop Window Help 30 20 10 -10 0 -20 -30 Foucault Pendulum, Position of Q -30 -20 -10 0 10 20 30 ex position (m)