482 KENNELLY AND AFFEL. 



eH Reluctance of Magnetic Circuit to alternating mmfs. (oersteds). 



r Equivalent motional resistance of a diaphragm, (dynes/kine) . 



r In theory of equivalent mass, the radius of a point on diaphragm. 



(cm). 

 pi Superficialdensity of diaphragm, (gm/sq. cm.) 



s Stiffness constant of a diaphragm, (dynes per cm.) 



t Time elapsed from a certain epoch . (seconds) . 



vmf. Contraction for vibromotive force, or alternating mechanical 



force tending to set up vibration, (dynes Z ). 

 W Maximum cyclic kinetic energy of diaphragm, (ergs). 



Wr Maximum cyclic kinetic energy of an annulus of width dr, and 



radius r. (ergs). 

 X Reactance of receiver winding, diaphragm damped, (absohms or 



ohms). 

 X* Reactance of receiver winding, diaphragm free, (absohms or 



ohms) . 

 XY Cartesian rectangular coordinates in a plane. 



X Vibratory displacement of a diaphragm, at any time, from its 



static position of rest. (cm). 

 Xm Maximum cyclic vibratory displacement of diaphragm at any 



frequency, (cm). 

 Xo Maximum cyclic vibration amplitude at center of diaphragm. 



X Vibratory velocity of a diaphragm at any time, (kines Z ). 



Xm Maximumcyclic vibratory velocity of diaphragm, (kines). 



X Vibratory acceleration of a diaphragm at any time, (kines/sec). 



Xi Initial velocity of a simple vibrator subject to damping, (kines) . 



xh xh x\ Maximum cyclic displacements at mid-radii of annular diaphragm 

 segments, (cm). 



Xr Vibrational amplitude of diaphragm at radius r, and any instant 



(cm). 



Z Motional impedance of a receiver at any frequency, (absohms Z ) . 



Zm Zms Maximum or diametral amplitude of motional impedance at 



resonance, (absohms). . 



z = r + jz Mechanical impedance of diaphragm, (dynes/kine Z ) • 



w Angular velocity of vibratory simple-harmonic motion (radians/ 



sec). 



wo Angular velocity of vibratory simple-harmonic motion at reso- 



nance (radians/sec). 



co' Free angular velocity in presence of damping, (radians/sec.) 



woi Resonant angular velocity of a loaded diaphragm, (radians/sec.) 



Z Sign of a complex quantity. 



<^5 Symbol for "cycles-per-second." 



