The value of flux involved m the e.m.f. equation of a transformer is____________?

A. average value
B. r.m.s. value
C. maximum value
D. instantaneous value

Silicon steel used in lamination’s mainly reduces___________?

A. hysteresis loss
B. eddy current losses
C. copper losses
D. all of the above

Helical coils can be used on___________?

A. low voltage side of high kVA transformers
B. high frequency transformers
C. high voltage side of small capacity transformers
D. high voltage side of high kVA rating transformers

Harmonics in transformer result in___________?

A. increased core losses
B. increased I2R losses
C. magnetic interference with communication circuits
D. all of the above

The core used in high frequency transformer is usually___________?

A. copper core
B. cost iron core
C. air core
D. mild steel core

Solid Grounding is used for Voltages?

A. Above 220 kv
B. Above 11kv
C. Below 660 v
D. Below 115 v

Which of the following has no units?

A. Permeability
B. Moment of a magnet
C. Magnetic susceptibility
D. Permittivity

If 1 A current flows in a circuit, the number of electrons flowing through this circuit is

A. 0.625 × 1019
B. 1.6 × 1019
C. 1.6 × 10-19
D. 0.625 × 10-19

Instantaneous power in inductor is proportional to the

A. product of the instantaneous current and rate of change of current.
B. square of instantaneous current.
C. square of the rate of change of current.
D. Temperature of the inductor.