Question is ⇒ In dc tacho generators used for measurement of speed of shaft, frequent calibration is necessary because, Options are ⇒ (A) contacts wear off, (B) strength of permanent magnet decreases with age, (C) armature current produces heating effect, (D) there is back emf, (E) , Leave your comments or Download question paper.

Question is ⇒ In dc tacho generators used for measurement of speed of shaft, frequent calibration is necessary because, Options are ⇒ (A) contacts wear off, (B) strength of permanent magnet decreases with age, (C) armature current produces heating effect, (D) there is back emf, (E) , Leave your comments or Download question paper. Previous question Next question


Q1.	In dc tacho generators used for measurement of speed of shaft, frequent calibration is necessary because
A.	contacts wear off [Wrong Answer]
B.	strength of permanent magnet decreases with age [Correct Answer]
C.	armature current produces heating effect [Wrong Answer]
D.	there is back emf [Wrong Answer]
View Answer 2 -1 Explanation:- Answer : B Discuss it below : !! OOPS Login [Click here] is required to post your answer/result Help other students, write article, leave your comments

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