Coefficients of Mutual Induction. 

 Fisr. 4. 



127 



30 

 28 



26 



a 



•2 24 

 o 







5 20 



1 



«M 18 

 o 



1 16 



'3 



352? 





















fi 







































I ■""■/*¥ 



















FHK 



81 



















fiBBB 



















^wwL^srfeii^ 





































HI 













a3 14 

 o 

 O 



J 1 12 



© 



X 10 

 m 



1 8 



O 6 



4 









■1 BIS 



















K 



SHH 



















fifll 



















39 



















BBS 





















^ "^%v'i , §*p* 









2 



A 





















3 4 5 6 7 8 9 10 11 12 13 

 Abscissae x 2= Distances between centres of Coils. 



14 15 16 



where ordinates denote values of M and abscissae distances 

 between the centres of the coils. 



B. Induction- Coil, by Apps, capable of giving a 7-inch 

 spark in air (presented to the University College Laboratory 

 by Mr. J. Rose-Innes, B.Sc). Length of secondary coil 

 21 cm., diameter (measured outside velvet covering) 11*3 cm. 

 Resistance of primary wire = 0*278 ohm (atl6°'5); resistance 

 of secondary wire 7394 ohms (at 16°-5). Battery, 1 Grove. 

 q~lSb'6; ? y = 0"58 (about). Condenser, 4*926 microfarads. 



Ohms. 



pr 



r. p. 



(absolute units) 



27 7394 + 1550 



2-415 x 10 23 



28 +1250 



2*420 



29 + 940 



2-417 



30 + 650 



2*413 



31 + 390 



2-413 



32 + 150 



2-414 



Mean value of M/C = 



= 2-415 xlO 23 



