Question

QUESTION 2 The voltage of an AC generator is controlled by? Increasing or decreasing the field current Increasing or decreasing the armature current The number of slip rings QUESTION 3 The frequency of an AC generator is unknown. We know the number poles which 6 and we know the speed n which is 1200rpm. What is the frequency? 602. 50Hz 1200HZ QUESTION 4 The frequency of an AC generator is unknown. We know the number poles which 6 and we know the speed n which is 800rpm. What is the frequency? 40Hz 50Hz

Answer 1

Question 2
Voltage of an AC generator is controlled by increasing or decreasing the field current.
Hence first choice is correct.

Question 3
The relation between frequency and speed is
N=(120f/p)
Where N is speed in rpm
f is frequency
P is number of poles.
Hence f=(NP/120)
Calculating f=60 hz
Hence first choice is correct.

Question 4
From previous question calculating f=40 hz.
Hence first choice is correct.

Question 5
Brushes and slip rings are used
Hence first choice is correct

Question 6
A field coil .
First choice is correct.

Question 7
The armature coil is fixed on the stator.

Question 8
Now from N=(120f/P)
Calculating N=3000 rpm

Question 9
Field.

Question 10
Again from formula
f = (NP/120)
Calculating f=50 Hz

Question 11
Armature coil is fixed on the rotor

Question 12
Armature

Question 13
50 Hz

Question 14
1.732 times greater than the phase voltage

Question 15
N=(120f/P)
P=120f/N
Calculating P=30 hence
15 pole pairs will be there .