Exam 1: Transformer Fundamentals and Operation

A transformer core is laminated to

The path of a magnetic flux in a transformer should have

A common method of cooling a power transformer is

The permissible flux density in case of cold rolled grain oriented steel is around

The no-load current drawn by transformer is usually what per cent of the full-load current ?

In a transformer routine efficiency depends upon

Sumpner's test is conducted on trans-formers to determine

The no load current in a transformer lags behind the appliedvoltage by an angle of about

A transformer transforms

Which winding in a transformer has more number of turns ?

Primary winding of a transformer

The dielectric strength of transformer oil is expected to be

The efficiency of a transformer will be maximum when

The purpose of providing an iron core in a transformer is to

Which of the following does not change in a transformer ?

No-load current in a transformer

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

Efficiency of a power transformer is of the order of

The degree of mechanical vibrations produced by the laminations of a transformer depends on

In a given transformer for given applied voltage, losses which remainconstant irrespective of load changes are