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14th October 2016, 03:50 PM
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| Re: DMRC Junior Engineer Electrical Books
Ok, here I am suggesting you some best books of Electrical of DMRC Junior Engineer exam. DMRC Junior Engineer exam Electrical books DMRC Junior Engineer Exam(Electrical,Mechanical,Civil))  DMRC Exam for Jr. Engineer (Electrical) Guide + Practice Workbook (Theory + Exercise + 10 Practice Sets) Paper I & II (Old Edition)  Kiran's DMRC Technical Exam Electrical & Electronics Junior Engineer Exam Guide - Cum - Practice Work Book - English  DMRC (Delhi Metro Rail Corporation) Junior Engineer Electrical Trade Bharti Pariksha  DMRC Junior Engineer exam Electrical questions Transformer 1. A transformer transforms a. frequency b. voltage c. current d. voltage and current 2. Which of the following is the basic element of transformer a. core b. primaryb winding c. secondary winding d. mutual flux 3. In an ideal transformer a. winding has no resistance b. core has no losses c. core has infinite permeanility d. all of the above 4. The maun purpose of using core in a transformer is to a. decrease iron losses b. prevent eddy current losses c.ilininate magnetic hysteresis d. decrease reluctance of comman magnetic circuit 5. Transformer cores are laminated in order to a. simplify its construction b. minimise eddy current losses c. reduce cost d. reduce hysterisis loss 6. A transformer having 1000 primary turns is connected to a 250 volt ac supply, for a secondary voltafge of 400 volt, the no. secondary turns should be a. 1600 b. 250 c. 400 d. 1250 7. The primary and secondary induced emf E1 & E2 in a 2 winding transformer are always a. equal in magnitude b. antiphase with each other c. Inphase in each other d. determine by load on transformer secondary 8. A step up transformer increases a. voltage b. current c. power d. frequency 9. The primary and secondary windings of an two winding transformer always have, a. different no of turns b. same size of copper wire c. a common magnetic circuit d. separate magnetic circuit 10. In a transformer the leakage flux of each winding is proportional to the current in that winding because, a. Ohm's law applies to the magnetic circuit b. Leakage path do not saturate c. the two windings are electrically isolated d. mutual flux is confined to core 11. In a 2 winding transformer the emf per turn in secondary winding is always ..... .the induced emf per turn in primary a. equal to k times b. equal to 1/k times c. equal to c. greater than 12. In a relation to a transformer the rayio 20/1 ; indicates that a. there are 20 turns on primary and 1 turn on secondary b. secondary voltage is 1/20 th of primary voltage c. primary current is 20 times greater than secondary surrent d. for every 20 turns on primary there is 1 turn on secondary |