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IOWA ACADEMY OF SCIENCE 



Thus we would expect that the number of vibrations executed 

 between any two amplitudes should vary inversely as the 

 length, if the above assumptions are correct. 



Two specimens of wire Xo. 4 were employed in this experi- 

 ment, one showing curves of type II and the other, curves of 

 type III. The results of the wire in state II will be discussed 

 first. The lengths used were 30, 23, 15 and 8.9 cms. Figure 37 



ICO 



200 TOO 



Vibration Numkr. 

 Fig. 3 7. 



400 



shows the vibration number-amplitude curves for the four 

 lengths. The number of vibrations between any two common 

 amplitudes per unit length can be interpolated from the 

 curves. 



It was found that there was essentially a constant ratio be- 

 tween the vibrations of any two curves, throughout the life of 

 the vibrations. Table III gives some of the interpolated values 

 from the four curves. The first column gives the lengths- and 

 each successive column gives the number of vibrations between 

 the amplitudes given in the parentheses. 



