S E S S I O N S MANTEL CLOCK Forestville, Connecticut / USA (1900) ******************************************************************** The clock came in a shaky case, was not working and the pendulum was missing. After cleaning and oiling a temporary pendulum was made out of a FORCEPS. After hours of fine tuning the clock worked again! To find the right pendulum sequence, a MAGNET was placed on the forceps and LONG NAILS are added and adjusted until the frequence was right and the clocktime precise. The ALARM has its own wind-up and its own bell situated on the left side. The Alarm is triggert by a wire from the CENTER WHEEL. The ALARM is settable by the CENTER WHEEL for 1 .. 12 hours in the future. The housing was cleaned, glued, nailed and looks nice again. A HONEY GLASS CUP was placed on the magnet to show a "real" pendulum. Next step is to build an adjustable pendulum ... PENDULUM in Theory & Pratice - A TEST -------------------------------------------------------------------- The "IDEAL PENDULUM" has its mass concentrated in a point, hanging on a long thread of length L [m]. The full swing (tick-tack) T [sec] is independent from its mass - but dependent from the gravitational constant G [ m / sec2 ] of its location: T = 2π * sqrt( L / G ) ===>> L = G * ( T / 2π )2 The temporary pendulum, what gives a quite precise clock time, count 60 full swings in 50 seconds ... L = 9.81 [ m / sec2 ] * ( 50 [sec] / ( 2π * 60 ))2 = 0.17256 [m] = 17.3 [cm] =========== WOW! - This is a pretty good result for the construction of the FINAL PENDULUM: The "MASS" (necessary for the "Momentum") has to be located and adjustable around 17 cm from its angle-point ... Back to SESSIONS Main Page impressum: ******************************************************************** © C.HAMANN http://public.BHT-Berlin.de/hamann 04/27/11 |