ELECTRONICS CHAPTER 6 1

What is the current flow in the line feeding a resonant circuit?

• Maximum

• Half

• Minimum

• Zero

The reciprocal of the power factor is called

• figure of merit

• quality factor

• magnification factor

• reactive power factor

A two coil de generator requires ________ number of commutator segments.

• One

• Two

• Four

• Eight

The type of prime mover specially designated for high speed alternators is the

• Steam turbine

• Water turbine

• Diesel turbine

• All of these

A DC generator uses _____ to produce de voltage rather than ac voltage at its output terminals.

• Slip rings

• Split rings

• Commutator

• Any of these

To determine the equivalent winding resistance and reactance, _______ is commonly performed on a transformer.

• short-circuit test

• blocked-rotor test

• paraffin test

• open-circuit test

A voltage step up transformer considered a current transformer?

• Step down

• Step up

• 1:1

• Any of these

Power lost in a magnetic material when flux density changes

• Eddy current effect

• Corona effect

• Copper loss

• Core loss

For a relay, the pick up current is defined as

• The maximum current rating of the coil

• The minimum relay coil current required to keep a relay energized

• The minimum relay coil current required to energize a relay

• The minimum current in the switching contacts

The generated voltage can be increased by

• Increasing the field current

• Decreasing the field current

• Decreasing the speed

• None of these