Synchronous Generator MCQs Part 9

Synchronous Generator MCQs Part 9

When the speed of alternator is reduced by half, the generated EMF will become

When the speed of alternator is reduced by half, the generated EMF will become

1. One-fourth
2. Half
3. Twice
4. Four times

Correct answer: 2. Half

The primary reason for placing field winding on the rotor in an alternator

The primary reason for placing field winding on the rotor in an alternator:

1. Large current in stator
2. Large power in stator
3. Small power in the field circuit
4. Insulation of high voltages is easier on stator than on rotor

Correct answer: 4. Insulation of high voltages is easier on stator than on rotor

In an alternator, the reactance EMF

In an alternator, the reactance EMF:

1. Is in phase with current
2. Leads the current by 90°
3. Lags behind current by 90°
4. None of the above

Correct answer: 2. Leads the current by 90°

For a 4-pole machine, 1 mechanical degree corresponds to how many electrical degrees

For a 4-pole machine, 1 mechanical degree corresponds to how many electrical degrees

1. 2
2. 4
3. 8
4. None of these

Correct answer: 1. 2

Low-speed alternators are driven using

Low-speed alternators are driven using

1. Steam engines
2. Steam turbines
3. Hydraulic turbines
4. None of these

Correct answer: 3. Hydraulic turbines