38 
133-7, 133°7 seconds. The mean value 7'= 1-339 agrees very closely with that 
deduced from the statical experiments. 
In the instrument shown in Fig. 3, p is adjusted to be 40:00 cm. 
Dr Searle, Experiment on the harmonic motion, ete. 
Width of inertia bar=24d =1°60 cm. 
Moment of inertia of bar= K=}M (L? + A*)=9°894 x 10* gm. cm.?. 
Distance from scale to nearer side of pivot= 39-92 cm. 
Diameter of pivot =0°38 cm. 
Hence p=39:92+4 x 0°38=40'11 cm. t. 
Diameter of cylinder= D=3:15 cm. 
Diameter of thread =d=0:03 cm. 
Mean value of 6/m=1°428 x 10-3 radians per gm. 
D+d 981 x 3°18 ec 
Hence, p= 2 a ye as 10-3 = 2-185 x 10° dyne-cm. per radian. 
K oe x 10! 
Thus, by (1), T=270 Je = Ug 2-185 x 108 = 1°338 sec. 
Direct observations with a good stop-watch gave 100 vibrations in 1342, 
+ In the goniometer used in this experiment p was not capable of adjustment. 
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