Cosidering about electromagnetic disc in elctromagnetic relays..there is dots on the disc and the disc is not unifrorm(not circular)..and also some cutout is povided on the disc..any special reason for this..
hi u also keep triangular or sq.. shape discs in electromagnetic relays......... You can Refer Electrical Measurements by A.K Sahney. Very Intelligent Question.. i think u r 30y in industry........ all the best.......