PSC Junior Instructor – Electrician Solved Paper 2015 – Part 4

PSC Junior Instructor – Electrician Solved Paper 2015 – Part 4

Question 76:-To test an armature for the short circuited coils, ________ is used along with the growler.
A:-milli-voltmeter
B:-hacksaw blade
C:-ohm meter
D:-meggar
Correct Answer:- Option-B

Question 77:-The type of fire extinguisher used where liquified gas is on fire is
A:-water filled fire extinguisher
B:-dry powder extinguisher
C:-foam type fire extinguisher
D:-carbon dioxide fire extinguisher
Correct Answer:- Option-B

Question 78:-Earthing one of the wires of electrical system, to limit the maximum voltage to earth under normal operating conditions is known as
A:-equipment earthing
B:-system earthing
C:-generator earthing
D:-substation earthing
Correct Answer:- Option-B

Question 79:-To measure the earth electrode resistance, the current and pressure spikes of the earth resistance tester are to be driven into the ground at a distance of ______ from the main electrode under test.
A:-20m and 10m apart respectively
B:-25m and 12.5m apart respectively
C:-20m and 10m apart respectively in a straight line
D:-25m and 12.5m apart respectively in a straight line.
Correct Answer:- Option-D

Question 80:-The type of joint used for overhead lines for tapping the electrical energy perpendicular to the service line is
A:-knotted tap joint
B:-aerial tap joint
C:-tee joint
D:-britannia tee joint
Correct Answer:- Option-D

Question 81:-According to BIS and NEC, the clearance between the bottom point of the ceiling fan and the floor shall not be less than
A:-2.5m
B:-2.75m
C:-2.25m
D:-2.4m
Correct Answer:- Option-D

Question 82:-If firing angle in an SCR rectifier is increased, the output is
A:-remains same
B:-SCR is turned off
C:-decreased
D:-increased
Correct Answer:- Option-C

Question 83:-Which electrode of the CRT mainly controls the brightness of the image on the screen?
A:-Anode
B:-Cathode
C:-Control grid
D:-Focusing electrodes
Correct Answer:- Option-C

Question 84:-Efficiency of a transformer is maximum, when
A:-no load loss is equal to full load loss
B:-hysteresis loss is equal to eddy current loss
C:-copper loss is equal to eddy current loss
D:-copper loss is equal to iron loss
Correct Answer:- Option-D

Question 85:-For the parallel operation of two transformers, the phase sequence must be identical, otherwise, during the cycle
A:-when secondaries are loaded, it will produce unequal loading conditions
B:-impossible to take the full load output without excessive heating of one of the transformer
C:-each pair of phases will be open circuited
D:-each pair of phases will be short circuited
Correct Answer:- Option-D

Question 86:-A two layer lap wound 4 pole generator with 16 coils will have a pole pitch of
A:-32
B:-16
C:-8
D:-4
Correct Answer:- Option-C

Question 87:-The maximum safe temperature for class F insulating material is
A:-155°C
B:-130°C
C:-120°C
D:-180°C
Correct Answer:- Option-A

Question 88:-The ratio of intensity of magnetisation to the magnetising force is known as
A:-permeability
B:-permittivity
C:-susceptibility
D:-magnetic potential
Correct Answer:- Option-C

Question 89:-While testing the field coil connections by compass method, the DC voltage to be applied to the field coil is
A:-10 to 20% of rated voltage
B:-the rated voltage
C:-60 to 70% of rated voltage
D:-200% of rated voltage
Correct Answer:- Option-A

Question 90:-The relays which are capable of maintaining their contacts in the last assumed position after the power is cut off are
A:-latching relays
B:-thermal relays
C:-reed relays
D:-elctro-mechanical relays
Correct Answer:- Option-A

Question 91:-In large motor generator sets, the AC motor used is usually
A:-squirrel cage type induction motor
B:-wound rotor type induction motor
C:-synchronous motor
D:-universal motor
Correct Answer:- Option-C

Question 92:-A watt meter measures the
A:-Apparent power
B:-Active power
C:-Reactive power
D:-Power factor
Correct Answer:- Option-B

Question 93:-A series resonant circuit is known as acceptor circuit, because its ______ will be maximum
A:-voltage
B:-current
C:-power factor
D:-frequency
Correct Answer:- Option-B

Question 94:-With two watt meter method of 3 phase power measurement, if one watt meter gives negative indication, then, the power factor will be
A:-unity
B:-zero
C:-more than 0.5
D:-less than 0.5
Correct Answer:- Option-D

Question 95:-A moving coil milliammeter having a resistance of 10 ohm gives full scale deflection, when a current of 5mA is passed through it. If the instrument to be used to measure a current up to 1A, then
A:-a resistance of 0.502 ohm must be connected in series with the ammeter
B:-a resistance of 0.502 ohm must be connected in series with the load
C:-a resistance of 0.502 ohm must be connected in parallel to the ammeter
D:-a resistance of 0.502 ohm mus be connected in parallel to the load
Correct Answer:- Option-C

Question 96:-The instrument which give the value of quantity to be measured in terms of deflection and instrument constants are
A:-secondary instruments
B:-indicating instruments
C:-integrating instruments
D:-absolute instruments
Correct Answer:- Option-D

Question 97:-A measuring instrument is enclosed inside an iron case. This is for protecting the measuring mechanism from
A:-heat
B:-magnetic flux
C:-static electricity
D:-hysteresis effect
Correct Answer:- Option-B

Question 98:-The cell voltage of a Lithium cell is
A:-2.1 to 2.6V
B:-2.5 to 3.6V
C:-1.2 to 1.4 V
D:-1.5V
Correct Answer:- Option-B

Question 99:-The illumination is directly proportional to the cosine of the angle made by the normal to the illuminated surface with the direction of the incident flux. This statement is associated with
A:-Macbeth’s law of illumination
B:-Bunsen’s law of illumination
C:-Lambert’s cosine law
D:-Plank’s law
Correct Answer:- Option-C

Question 100:-In a drill, ______ helps to form the cutting edge.
A:-Land
B:-Shank
C:-Tang
D:-Flutes
Correct Answer:- Option-D

PSC Junior Instructor – Electrician Solved Paper 2015 – Part 1

PSC Junior Instructor – Electrician Solved Paper 2015 – Part 2

PSC Junior Instructor – Electrician Solved Paper 2015 – Part 3

PSC Junior Instructor – Electrician Solved Paper 2015 – Part 4