Conical pendulum

Monumental conical pendulum clock by Farcot, 1878

A conical pendulum consists of a weight (or bob) fixed on the end of a string or rod suspended from a pivot. Its construction is similar to an ordinary pendulum; however, instead of swinging back and forth along a circular arc, the bob of a conical pendulum moves at a constant speed in a circle or ellipse with the string (or rod) tracing out a cone. The conical pendulum was first studied by the English scientist Robert Hooke around 1660[1] as a model for the orbital motion of planets.[2] In 1673 Dutch scientist Christiaan Huygens calculated its period, using his new concept of centrifugal force in his book Horologium Oscillatorium. Later it was used as the timekeeping element in a few mechanical clocks and other clockwork timing devices.[3][4]

  1. ^ O'Connor, J.J.; E.F. Robertson (August 2002). "Robert Hooke". Biographies, MacTutor History of Mathematics Archive. School of Mathematics and Statistics, Univ. of St. Andrews, Scotland. Retrieved 2009-02-21.
  2. ^ Nauenberg, Michael (2006). "Robert Hooke's seminal contribution to orbital dynamics". Robert Hooke: Tercentennial Studies. Ashgate Publishing. pp. 17–19. ISBN 0-7546-5365-X.
  3. ^ Beckett, Edmund (Lord Grimsthorpe) (1874). A Rudimentary Treatise on Clocks and Watches and Bells, 6th Ed. London: Lockwood & Co. pp. 22–26.
  4. ^ "Clock". Encyclopædia Britannica, 9th Ed. Vol. 6. Henry G. Allen Co. 1890. p. 15. Retrieved 2008-02-25.