Question is ⇒ If a transformer is switched on to a voltage more than the rated voltage, Options are ⇒ (A) its power factor will deteriorate, (B) its power factor will increase, (C) its power factor will remain unaffected, (D) its power factor will be zero, (E) , Leave your comments or Download question paper.

Question is ⇒ If a transformer is switched on to a voltage more than the rated voltage, Options are ⇒ (A) its power factor will deteriorate, (B) its power factor will increase, (C) its power factor will remain unaffected, (D) its power factor will be zero, (E) , Leave your comments or Download question paper. Previous question Next question


Q1.	If a transformer is switched on to a voltage more than the rated voltage
A.	its power factor will deteriorate [Correct Answer]
B.	its power factor will increase [Wrong Answer]
C.	its power factor will remain unaffected [Wrong Answer]
D.	its power factor will be zero [Wrong Answer]
View Answer 18 -5 Explanation:- Answer : A Discuss it below : Charanpreet Said on 2016-03-10 08:09:54 let p=100 watt, v=230 at unity p.f p=vicos 100=230i1 ì=.434 now voltage should be doubled or increase but other parameters should be same so we find out R=V/I 230/.434=523 R= 523 V=300,R=523 I=.57 again P=vìcos 100=300.57cos cos=.58 !! OOPS Login [Click here] is required to post your answer/result Help other students, write article, leave your comments

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