1
Which winding in a transformer has more number of turns ?
Answer: High voltage winding
Questions
2
Primary winding of a transformer
Answer: could either be a low voltage or high voltage winding
3
A transformer cannot raise or lower the voltage of a D.C. supply because
Answer: Faraday’s laws of electromagnetic induction are not valid since the rate of change of flux is zero
5
In the transformer following winding has got more cross-sectional area
Answer: Low voltage winding
6
While conducting short-circuit test on a transformer the following side is short circuited
Answer: Low voltage side
7
Which of the following is not a part of transformer installation ?
Answer: Exciter
8
The purpose of providing an iron core in a transformer is to
Answer: decrease the reluctance of the magnetic path
9
No-load current in a transformer
Answer: lags behind the voltage by about 75°
10
The efficiency of a transformer will be maximum when
Answer: copper losses = iron losses
11
The permissible flux density in case of cold rolled grain oriented steel is around
Answer: 1.7 Wb/m2
12
Sumpner’s test is conducted on trans-formers to determine
Answer: temperature
14
No-load on a transformer is carried out to determine
Answer: magnetising current and loss
15
The path of a magnetic flux in a transformer should have
Answer: low reluctance
16
The no-load current drawn by transformer is usually what per cent of the full-load current ?
Answer: 2 to 5 per cent
17
The degree of mechanical vibrations produced by the laminations of a transformer depends on
Answer: all of the above
19
In a transformer the energy is conveyed from primary to secondary
Answer: by the flux
