344 Prof. J. A. Fleming and Mr. J. E. Petavel t 



Fig. 10. — Intensity of Light from Centre of Arc. 



\ \ / Angle of Phase \ / ; 



180 / 270 



360 



Time 



>» *■ 



Frequency =50 ~. Length of arc=032 cm. (See Table IV. B.) 

 Fig. 11. — Intensity of Light from Centre of Arc. 



Frequency=50 ~. Length of arc=l'2 cm. (See Table V. A.) 



