Electrical 2 (6.7.8.9)

An AC generator is an electric generator that converts mechanical energy in to

• rotational energy
• ternating electrical ener
• potential energy
• none of the above

The relation of between frequency and speed is

• Ns=120 x f/P
• Ns=120 x P/f
• Ns=120 x f/A
• Ns=120 x f/2

The frequency of voltage generated in an alternator depends on

• number of poles
• speed of alternator
• both (a) and (b)
• type of winding

The frequency of voltage generated by an alternator having 4- pole and rotating at 1800 r.p.m is hertz.

• 60
• 7200
• 120
• 450

The power factor of an alternator is determined by its

• speed
• load
• excitation
• prime mover

Which of these types of motor is self starting?

• dc motor
• nle phase induction mot
• 3 phase induction motor
• ac motor

the direction of rotation of the single phase motor can be reversed by

• ng connections of both w
• g connections og startin
• using a revers switch
• revesing supply connection

one of the characteristics of a single phase motor is that it

• is self starting
• is not self starting
• requires only one winding
• an rotate in one direction on

after the staring winding of single phase induction motor is disconnected from supply it continues to run only on ……..

• Rotor
• compensating
• field
• running

the starting winding of a single phase motor is placed in the

• Rotor
• Stator
• Armature
• field