Kerala Public Service Commission Electrician Paper 2016
Repulsion motor is provided with
(a) Commutator
(b) Centrifugal switch
(c) Capacitor
(d) Squirrel cage rotor
Whenever a poly phase motor is loaded the
(a) induced emf in the rotor increases and its frequency falls
(b) induced emf in the rotor increases and its frequency rises
(c) induced in the rotor remains constant
(d) induced emf in the rotor decreases and its frequency increases
For three resistance are connected in three phase, the power consumed will be more in ________connection
(a) star delta
(b) star
(c) delta
(d) delta-star
Synchronous motors run on leading power factor when connected in
(a) under excitation
(b) rated excitation
(c) fully loaded
(d) over excitation
The output voltage of a solar cell is approximately
(a) 1.2 V
(b) 0.5 V
(c) 2.1 V
(d) 3.0 V
Slip rings are generally made of
(a) phosphor bronze
(b) aluminium
(c) copper
(d) carbon
The hydrometer reading of fully charged lead acid battery
(a) 1.2
(b) 1.5
(c) 1.11
(d) 1.26
In induction motor percentage slip is maximum at
(a) low speed
(b) medium speed
(c) stand still condition
(d) synchronous speed
Economiser is a part of
(a) hydel PS
(b) nuclear PS
(c) thermal PS
(d) diesel PS
The crawling in an induction motor is caused by
(a) improper design of the machine
(b) low voltage supply
(c) high load
(d) harmonics developed in the motor
The commutator segments are placed in
(a) rotor
(b) stator
(c) armature
(d) field
Reduction in the capacitance of capacitor start motor results in reduced
(a) noise
(b) starting torque
(c) speed
(d) armature reaction
In an ac circuit the ratio of kW/kVA represents
(a) power factor
(b) load factor
(c) starting torque
(d) diversity factor
The unit of inductance is
(a) OHM
(b) MHO
(c) HENRY
(d) FARAD
Ear to ear resistance of human body
(a) 400
(b) 1 kilo ohms
(c) 650 ohms
(d) 100 ohms
Centrifugal switches is provided for disconnecting the auxiliary winding in a
(a) capacitor run motor
(b) capacitor start motor
(c) reluctance motor
(d) hysteresis motor
Transformer core is laminated to
(a) reduce the copper loss
(b) reduces the eddy current loss
(c) reduces the core loss
(d) hysteresis loss
Which type of loss is NOT common to transformer and rotating machines ?
(a) eddy current loss
(b) copper loss
(c) hysteresis loss
(d) windage loss
The difference between the synchronous speed and the actual speed of an induction motor is known as
(a) Slip
(b) regulation
(c) back lash
(d) lag
Three resistances of 30, 15, 5 ohms are connected in parallel, their combined resistance will be
(a) greater than 30 ohm
(b) between 30 to 15 ohm
(c) less than 5 ohm
(d) between 15 to 5 ohm
Leave a Reply