In a given transformer for given applied voltage, losses which remain constant irrespective of load changes are______________?

A. friction and windage losses
B. copper losses
C. hysteresis and eddy current losses
D. none of the above

A common method of cooling a power transformer is_______________?

A. natural air cooling
B. air blast cooling
C. oil cooling
D. any of the above

In a transformer routine efficiency depends upon_____________?

A. supply frequency
B. load current
C. power factor of load
D. both B. and (c)

In the transformer the function of a conservator is to_______________?

A. provide fresh air for cooling the transformer
B. supply cooling oil to transformer in time of need
C. protect the transformer from damage when oil expends due to heating
D. none of the above

Natural oil cooling is used for transformers up to a rating of____________?

A. 3000 kVA
B. 1000 kVA
C. 500 kVA
D. 250 kVA

Power transformers are designed to have maximum efficiency at___________?

A. nearly full load
B. 70% full load
C. 50% full load
D. no load

The maximum efficiency of a distribution transformer is____________?

A. at no load
B. at 50% full load
C. at 80% full load
D. at full load

Transformer breaths in when_______________?

A. load on it increases
B. load on it decreases
C. load remains constant
D. none of the above

No-load current of a transformer has_____________?

A. has high magnitude and low power factor
B. has high magnitude and high power factor
C. has small magnitude and high power factor
D. has small magnitude and low power factor

Spacers are provided between adjacent coils?

A. to provide free passage to the cooling oil
B. to insulate the coils from each other
C. both A. and (b)
D. none of the above