14 ELECTRICAL ENGINEERING PROBLEMS 



23. The flux in the annature of a bipolar, 110-volt, 6-kw. 

 generator is 3 X 10 6 , while that in the field is 3.9 X 10 6 . Required 

 the leakage coefficient. (J min.) 



24. In a bipolar, 110-volt, 4 kilowatt generator, the armature 

 density is 14,000 and the total flux 2.8 X 10 6 . The leakage 

 coefficient is 1 .25 ; required the area of the field magnet, if a density 

 of 12,000 be used. (3 min.) 



25. In a 50-kw., 110-volt, 4-pole generator the armature 

 density is 14,000, and the double cross-sectional area of the ring, 

 550 sq. cm. In the field-magnet ring the density is 12,000 and 

 the double area is 820 sq. cm.; required the leakage coefficient. 

 (2 min.) 



26. Given the leakage coefficient 1.32 and the armature flux 

 10.63 megamaxwells. The yoke of the dynamo is to be of cast 

 iron. Required the dimensions of its cross-section in inches for 

 B equal to 7200 if its length is to be twice its breadth. (4 min.) 





