Computer Programming MCQs

5739 MCQs  (Page 180 of 574)

Ageing of a selenium rectifier may change the output voltage by__________?
A. 5 to 10 per cent
B. 15 to 20 per cent
C. 25 to 30 per cent
D. None of the above
The metal rectifiers are preferred to valve rectifiers due to which of the following advantages ?
A. They are mechanically strong
B. They do not require any voltage for filament heating
C. Both (a) and (b)
D. None of the above
Which of the following statement is incorrect ?
A. Copper oxide rectifier is a linear device
B. Copper oxide rectifier is not a perfect rectifier
C. Copper oxide rectifier has a low efficiency
D. Copper oxide rectifier finds use in control circuits
On which of the following factors the number of phases for which a rectifier should be designed depend ?
A. the voltage regulation of the rec¬tifier should be low
B. in the output circuit there should be no harmonics
C. the power factor of the system should be high
D. the rectifier supply transformer should be utilized to the best ad-vantage