THE INDUCTION MOTOR. 



however, the bars are numerous enough to permit the representation 

 by a curve instead of a line composed of small vertical and horizontal 

 steps. The question we have now to investigate is : what is the mag- 

 netizing effect of the currents which are collectively represented by 

 the curve I ? In other words, if there were no other currents flowing 

 but those represented by the curve i, what would be the disposition 

 of the magnetic field produced by them? Positive ordinates of I 

 represent currents flowing upwards or towards the observer in Fig. 



FIG. 50. 



49, negative ordinates represent downward currents. The former 

 tend to produce a magnetic whirl in a counter clockwise direction, 

 and the latter in a clockwise direction. Thus the current in the bar 

 which happens at the moment to occupy the position b, will tend to 

 produce a field, the lines of which flow radially inwards on the right 

 of b, and radially outwards on the left of b. Similarly the current 

 in the bar occupying the position a, tends to produce an inward 



92 



