Demos by PIRA

  3A60.10Film : "Tacoma Narrows bridge collapse",silent, 4 min.
  3A60.24Driven oscillations in a multiple spring-mass system.
  3A60.40Driven harmonic oscillator: Motor driven mass on spring.
  3A60.50Unbalanced spinning wheel vibrates spring steel reeds.
  3A60.50Set of three coupled inverted pendulums on wood base.
  3A60.55Clock spring oscillator: Electrically driven and damped.
  3A60.60Inverted pendulum.