Which of the following is the main advantage of an auto-transformer over a two winding transformer?

The dielectric strength of transformer oil is expected to be______________?

A. lkV
B. 33 kV
C. 100 kV
D. 330 kV

The transformer lamination’s are insulated from each other by____________?

A. mica strip
B. thin coat of varnish
C. paper
D. any of the above

A good voltage regulation of a transformer means________________?

A good voltage regulation of a transformer means
A. output voltage fluctuation from no load to full load is least
B. output voltage fluctuation with power factor is least
C. difference between primary and secondary voltage is least
D. difference between primary and secondary voltage is maximum

A. 180°
B. 120″
C. 90°
D. 75°

A transformer cannot raise or lower the voltage of a D.C. supply because_______________?

A. there is no need to change the D.C. voltage
B. a D.C. circuit has more losses
C. Faraday’s laws of electromagnetic induction are not valid since the rate of change of flux is zero
D. none of the above

A. to provide coupling between primary and secondary
B. to increase the magnitude of mutual flux
C. to decrease the magnitude of mag-netizing current
D. to provide all above features