The first Foucault’s pendulum I ever saw was at the Franklin Institute in Philadelphia, the city where I was born. The pendulum hung in a stairwell. Its wire was attached to the ceiling four stories ...

A basic pendulum is a mass at the end of a string that swings back and forth. It seems simple, and it appears in most introductory physics textbooks. But it's not a trivial problem to solve for the ...

A Foucault pendulum, or Foucault's pendulum, named after the French physicist Leon Foucault, was conceived as an experiment to demonstrate the rotation of the Earth; its action is a result of the ...

A pendulum prepared perfectly inverted and motionless is a prototype of unstable equilibrium and corresponds to an unstable hyperbolic fixed point in the dynamical phase space. Here, we measure the ...