ELECTRICIAN

ELECTRICIAN

The electrical wiring in factories and industries
is done by.........,.
(a) Cleats
(b) Casing capping
(c) Surface metal conduit
(d) Surface PVC conduit
Answer: (c) Surface metal conduit

The magnetic operating limit of C-type of
MCB’s is..........times of the rated current.
(a) 5 to 10
(b) 20 to 30
(c) 3 to 5
(d) 10 to 20
Answer: (a) 5 to 10
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Which one of the following lamps has the
longest operating life?
(a) LED lamp
(b) Fluorescent tube light
(c) CFL
(d) Incandescent lamp
Answer: (a) LED lamp

When the Growler is connected with 230 V,
AC supply and armature is placed over it,
the arrangement behaves like a....................
(a) Potential Divider
(b) AC Motor
(c) Transformer .
(d) DC Bridge
Answer: (c) Transformer
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A motor normally fitted to a domestic
vacuum cleaner is.............motor.
(a) Universal
(b) Cage Induction
(c) Wound rotor
(d) Shunt Wound
Answer: (a) Universal

The type of single-phase induction motor
 having the highest power factor at full load
is....:..............
(a) Shaded pole type
(b) Split-phase type
(c) Capacitor-start type
(d) Capacitor-run type
Answer: (d) Capacitor-run type

The method of braking an induction motor by
interchanging the supply to two of the
stator phase windings is called..................
(a) Plugging
(b) Stopping
(c) Commutation
(d) Retarding
Answer: (a) Plugging

If a three phase induction motor is switched on with
one phase disconnected, the motor will ................
(a) Run at low speed
(b) Burn Out
(c) Run at High Speed
(d) Not Run
Answer: (b) Burn Out
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The running of induction motors at slow and
steady speed much less than the actual
speed  is known as.
(a) Crawling
(b) Damping,
(c) Sinking
(d) Ageing
Answer: (a) Crawling
The distribution of load between two alternators
operating in parallel can be changed by
changing...............
(a) Phase sequence .
(b) Field excitation of alternators
(c) Current direction
(d) Driving torques of prime movers
Answer: (d) Driving torques of prime movers