CHAPTEE XV 



INORGANIC RESPONSE RELATION BETWEEN STIMULUS AND 

 RESPONSE SUPERPOSITION OF STIMULI 



Relation between stimulus and response Magnetic analogue Increase of 

 response with increasing stimulus Threshold of response Superposition 

 of stimuli Hysteresis. 



Relation between stimulus and response. We have 

 seen what extremely uniform responses are given by 

 tin, when the intensity of stimulus is maintained constant. 

 Hence it is obvious that these phenomena are not 

 accidental, but governed by definite laws. This fact 

 becomes still more evident when we discover how 

 invariably response is increased by increasing the 

 intensity of stimulus. 



Electrical response is due, as we have seen, to a 

 molecular disturbance, the stimulus causing a distortion 

 from a position of equilibrium. In dealing with the 

 subject of the relation between the disturbing force and 

 the molecular effect it produces, it may be instructive 

 to consider certain analogous physical phenomena in 

 which molecular deflections are also produced by a 

 distorting force. 



Magnetic analogue. Let us consider the effect that 

 a magnetising force produces on a bar of soft iron. It 

 is known that each molecule in such a bar is an 



K 2 



