595 



oscillations of finite anipliduie, till at last the dipole changes its 

 form of motion and begins to rotate to the right or to the left ; at 

 tirst still noticeably irregularly, at last with constant velocity of 

 rotation. When we consult F'ig. 1, the continuous change of the 

 motion will become clear, particularly also the transition through 

 the singular motion GH. A complete oscillation corresponds in the 

 final state to a double rotation of the uniformly rotating dipole 



(0 ^ ^ ^ 4jr) : ABE. Hence if we wish to derive the kinetic energy 

 1\ of the uniform rotation by the aid of the "adiabatic relation" 

 from the mean kinetic energy 1\ of the original oscillatory motion, 

 we must take as corresponding period the time 



4jr 



(6) 



where q^ is the constant velocity of rotation of the dipole ; so as 

 corresponding frequency 



V, = 



4jr 



Then according to (7) (I) and (3), we have 



(7) 



or also, as 



4jrT, rr\ h h 



Pill 



2 



h 



2 



(8) 



(9) 



