1- The primary and secondary of a transformer are coupl a) Electrically b) magnetically c) electrically and magnetically d) none of the above. 2- A transformer takes a current of 0.8A and absorbs 70W when the primary is connected to its n upply of 220V, 50Hz; the secondary being on open circuit. The magnetizing current will be --- a) 0.2A b) 0.43A c) 0.73A d) 0.6A e) none of the above 3- A transformer will have maximum efficiency at ------ a) full-load b) no-load c) half-full load d) none of the above 4- The iron loss in a certain transformer is 90W at 25Hz and 200W at 50Hz the flux density bei same, then the iron loss at 100Hz at the same flux density will be a) 480W b) 360W c) 440 d) none of the above

1- The primary and secondary of a transformer are coupl a) Electrically b) magnetically c) electrically and magnetically d) none of the above. 2- A transformer takes a current of 0.8A and absorbs 70W when the primary is connected to its n upply of 220V, 50Hz; the secondary being on open circuit. The magnetizing current will be --- a) 0.2A b) 0.43A c) 0.73A d) 0.6A e) none of the above 3- A transformer will have maximum efficiency at ------ a) full-load b) no-load c) half-full load d) none of the above 4- The iron loss in a certain transformer is 90W at 25Hz and 200W at 50Hz the flux density bei same, then the iron loss at 100Hz at the same flux density will be a) 480W b) 360W c) 440 d) none of the above

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.32MCQ

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