EASY PSC | Kerala PSC 008/2022 - Operator

Question 1

The unit of solid angle is :

A

radian

B

steradian

C

degree

D

none of the above

Question 2

What is the temperature co-efficient value of aluminium at 20° celcius ?

A

40.3×10^−4

B

40.3×10^−3

C

40.3×10^−2

D

40.3×10^−5

Question 3

Melting point of copper is :

A

1083°C

B

1183°C

C

983°C

D

1000°C

Question 4

One ampere-hour is equal to :

A

36000 coulombs

B

3600 coulombs

C

360 coulombs

D

36 coulombs

Question 5

The shape of warning sign is __________.

A

circular

B

square

C

triangular

D

rectangular

Question 6

Unit of M.M.F. is :

A

Maxwell

B

Lambda

C

Joule

D

Ampere turns

Question 7

What is the permeability of bismuth ?

A

0.00099988

B

0.99988

C

1.000999881

D

1.99988

Question 8

A

(A)

B

(B)

C

(C)

D

(D)

Question 9

Which type of capacitors are used in RF coupling circuits ?

A

tantalum

B

electrolytic

C

monolithic

D

metalized polypropylene

Question 10

The voltage of a simple voltaic cell is :

A

1.5 V

B

1.28 V

C

1.08 V

D

1.4 V

Question 11

The speed of electricity is :

A

2,97,842 km/s

B

2,97,842 km/m

C

2,97,842 km/hr

D

none of the above

Question 12

What is the resistance of the inductive coil takes 5 A current across 240 V, 50 Hz supply at 0.8 P.F. ?

A

48 W

B

42.5 W

C

38.4 W

D

26.6 W

Question 13

In a 3 phase system, if the active power is 4 kW and the apparent power is 5 kVA, calculate the reactive power.

A

1 kVAR

B

2 kVAR

C

3 kVAR

D

4 kVAR

Question 14

What is the di-electric strength in k.V/m.m. of asbestos at 208C ?

A

40

B

42

C

44

D

46

Question 15

Two wattmeter method is used to measure the power in __________ load.

A

resistive load

B

balanced load

C

un-balanced load

D

balanced and un-balanced load

Question 16

To magnetize a steel is difficult because of its :

A

high density

B

high retentivity

C

high permeability

D

low permeability

Question 17

What is the effect if one cell is connected with reverse polarity in a parallel combination circuit ?

A

voltage became zero

B

became open circuit

C

will get short circuited

D

no effect will function normally

Question 18

The depolarizer is used in dry cell is :

A

MNO2

B

MNO3

C

mercury sulphate

D

NH3

Question 19

Two batteries each of open circuit voltage 2 V and internal resistance of 2 ohm are connected in parallel to supply a load of 2 ohm the current supplied by the battery is :

A

0.33 A

B

2 A

C

0.8 A

D

1 A

Question 20

A 24 ohm and 8 ohm resistors are in parallel have a combined resistance of :

A

32 ohm

B

24 ohm

C

12 ohm

D

6 ohm

Question 21

The control force employed in an indicating instrument, which can be kept in any position is :

A

gravity control

B

eddy current control

C

fluid friction control

D

spring control

Question 22

If the meter constant mentioned in the meter is 1500 revolution/k.W.H., in one revolution, the energy consumption is :

A

40 watt-minutes

B

60 watt-minutes

C

100 watt-minutes

D

50 watt-minutes

Question 23

Maxwell-Wein bridge is used for measuring :

A

capacitance

B

dielectric loss

C

inductance

D

phase angle

Question 24

The line voltage of a delta-connected three-phase circuit is 415 V. The phase voltage is :

A

220 V

B

230 V

C

240 V

D

415 V

Question 25

In a 3 phase star connected resistive load the resistance of each phase is 50 ohm if one of the resistances is removed and 200 V supply is given the absorbed power will be :

A

200 W

B

400 W

C

800 W

D

600 W

Question 26

In Flemings left hand rule, forefinger indicates :

A

Direction of supply of voltage

B

Motion of the conductor

C

Direction of field

D

Direction of current flow

Question 27

A current transformer step up :

A

Voltage

B

Current

C

Power

D

Frequency

Question 28

Hunting occurs in :

A

Transformer

B

Induction motor

C

Synchronous motor

D

D.C. motor

Question 29

The system earthing is done at :

A

Domestic wiring

B

Godown wiring

C

Generating station

D

House wiring

Question 30

An example of cold cathode lamp is :

A

Neon lamp

B

Mercury vapour lamp

C

Fluorescent tube

D

Incandescent lamp

Question 31

Decimal equivalent of Hexadecimal number "D" is :

A

14

B

13

C

12

D

10

Question 32

Terminals of a IGBT are :

A

Base, Collector, Emitter

B

Emitter, Collector, Gate

C

Base 1, Base 2, Emitter

D

Drain, Source, Gate

Question 33

The capacity of Transformers are rated by its :

A

True power

B

Actual power

C

Apparent power

D

Reactive power

Question 34

Which circuits quick response type diazed fuses are used ?

A

Motor circuits

B

Heating circuits

C

Lightning circuits

D

Electronics circuits

Question 35

How many number of brushes are used in wave wound DC shunt generator ?

A

1

B

2

C

3

D

6

Question 36

A JFET is a __________ driven device.

A

Voltage

B

Current

C

Frequency

D

Power

Question 37

The radix of decimal number system is :

A

1

B

2

C

10

D

0

Question 38

As per BIS the shunt field winding terminals of a DC machine is marked :

A

B1 & B2

B

E1 & E2

C

F1 & F2

D

D1 & D2

Question 39

The V-curve of a synchronous motor is the relation between :

A

Applied voltage and back emf

B

Back emf and armature current

C

Back emf and power factor

D

Armature current & rotor field current

Question 40

Which transformer does not step up or step down the voltage ?

A

Auto transformer

B

Isolation transformer

C

Power transformer

D

Current transformer

Question 41

Binary value of 0101 is equivalent to decimal number :

A

5

B

7

C

4

D

3

Question 42

An SCR has __________ semiconductor layers.

A

1

B

2

C

4

D

3

Question 43

Ripple frequency of full wave bridge rectifier is :

A

F input

B

2 F input

C

4 F input

D

1/2 F input

Question 44

Which method of speed control is used to obtain above normal speed in DC series motor ?

A

Field taping method

B

Voltage control method

C

Field diverter method

D

Armature control method

Question 45

Which one is a Universal gate ?

A

OR

B

NOR

C

NOT

D

AND

Question 46

A UJT contains __________ PN junctions.

A

1

B

2

C

3

D

4

Question 47

The insulation resistance of a DC motor is measured in :

A

Mega volts

B

Mega watts

C

Mega ohms

D

Kilo ohms

Question 48

Which test is used to check whether the switches are connected in live wire or not ?

A

Continuity test

B

Open circuit test

C

Ground test

D

Polarity test

Question 49

Which electrical accessories is used for taking supply from a lamp holder ?

A

Ceiling rose

B

3 pin plug top

C

Adaptor

D

Two pin plug top

Question 50

An example of invertor gate is :

A

NAND

B

OR

C

NOT

D

AND

Question 51

What is the purpose of soldering on sheet metal joint ?

A

To avoid bend

B

To avoid crack

C

To avoid leak

D

To make strengthless

Question 52

Which part in the internal gear pump act as seal ?

A

Gears

B

Gasket

C

Sealing ring

D

Cresent shaped spacer

Question 53

Which rivet used in heavy structural work ?

A

Pan head rivet

B

Snap head rivet

C

Counter sunk rivet

D

Conical head rivet

Question 54

Which washers are commonly used for structural fabrication work ?

A

Flat washers

B

Punched washers

C

Tab washer

D

Toothed lock washer

Question 55

Which metal is very soft and heavy in sheet metal work ?

A

Lead

B

Black iron

C

Aluminium

D

Copper sheet

Question 56

Which hammer is suitable for riveting ?

A

Plastic hammer

B

Ball pein hammer

C

Cross pein hammer

D

Straight pein hammer

Question 57

Which key is used for easy fixing and removing ?

A

Feather key

B

Gib-head key

C

Hollow saddle key

D

Circular taper key

Question 58

Which type of nut required aligning the axle shaft hole and slot of the nut for locking ?

A

Castle nut

B

Chuck nut

C

Thumb nut

D

Self lock nut

Question 59

Which energy is converted in hydraulic pump ?

A

Thermal energy to hydraulic energy

B

Electrical energy to hydraulic energy

C

Pneumatic energy to hydraulic energy

D

Mechanical energy to hydraulic energy

Question 60

Which type of filter helps to protect the pump from fluid contaminations ?

A

Suction filter

B

Magnetic filter

C

Absorbent filter

D

Mechanical filter

Question 61

Which of the following is an insulator ?

A

Copper

B

Aluminium

C

Silver

D

PVC

Question 62

Which is a good conductor ?

A

Silver

B

Iron

C

Steel

D

Aluminium

Question 63

Which law states that “The current is directly proportional to the voltage and inversely proportional to the resistance” ?

A

Ohm"s law

B

Hook"s law

C

Boyle"s law

D

Newton"s law

Question 64

What is the material of negative plate in the lead acid battery ?

A

Antimony

B

Tin

C

Spongy lead

D

Lead peroxide

Question 65

Which instrument is prohibited to connect with live wire ?

A

Ammeter

B

Voltmeter

C

Ohm meter

D

Watt meter

Question 66

Which measuring instrument used to measure the ampere, volt and resistance ?

A

Watt meter

B

Energy meter

C

Galvano meter

D

Multi meter

Question 67

What is the unit of potential difference ?

A

Watt

B

Ampere

C

Ohm

D

Volts

Question 68

What is the advantage of free maintenance sealed battery ?

A

No need for check and top up distilled water

B

No need for recharging the battery

C

No chance of sulphation of battery terminals

D

No need of disconnect the terminals to remove battery

Question 69

Which is a temperature sensitive resistor ?

A

Diode

B

Thyristor

C

Thermistor

D

Transistor

Question 70

Which circuit the ballast resistor is used ?

A

Horn circuit

B

Wiper circuit

C

Flasher circuit

D

Headlamp circuit

Question 71

Which of the following is true about the thermodynamic cycle of a diesel engine ?

A

Constant volume cycle

B

Constant pressure cycle

C

Atkinson cycle

D

None of these

Question 72

What is the range of compression pressure of a typical petrol engine ?

A

90 to 150 PSI

B

400 to 550 PSI

C

500 to 700 PSI

D

None of these

Question 73

Which of the following is false about engine cooling system ?

A

Radiator pressure cap consists of a pressure valve which opens up when the pressure exceeds a pre-set value.

B

Vacuum valve on radiator pressure cap opens up to let the coolant in while the engine cools down.

C

ECM calculates coolant temperature value from the ECT sensor output.

D

Engine overheats if the thermostat valve is stuck open.

Question 74

In which of the following types of oil pumps does not use eccentric shafts or cams ?

A

External gear type pump

B

Rotor type pump

C

Vane type pump

D

Plunger type pump

Question 75

Which of the following statements is false about lubrication system ?

A

Oil cooler heats the oil when coolant temperature is greater than oil temperature.

B

All the oil reaching main oil gallery is filtered in Bypass oil filter system.

C

Dry sump lubrication system uses a separate tank to store oil.

D

Lubricant also helps in preventing blow by gases entering crankcase.

Question 76

Which of the following is false about fuel system ?

A

Air locking in the diesel fuel system will cause erratic running of engine.

B

Water in fuel system might damage fuel injectors.

C

An engine can be started without the signal from Crank position sensor (CKP) input.

D

Injection pressure in CRDi engines vary from 200 to 2000 bars.

Question 77

Which of the following type of pump needs more frequent overhaul frequency than others under similar operating conditions ?

A

Submersible pump

B

Vertical turbine pump

C

Centrifugal pumps

D

All of these pumps have broadly the same maintenance frequency

Question 78

Which of the following is true about the Submersible pumps ?

A

Single stage pumps are preferred over Multistage pumps in water wells and oil wells

B

They are centrifugal pumps operating in a vertical position

C

The energy conversion taking place at the pump diffuser is kinetic energy into pressure energy

D

All are true

Question 79

Which of the following is false about Jet pumps ?

A

It has no reciprocating parts

B

The motor and pump cannot be offset from the well

C

Suction pipe is connected to the nozzle chamber

D

All are false

Question 80

Which of the following is wrong ?

A

A locked pump shaft will result in blown pump fuse

B

Clogged strainer will result in reduced pump capacity

C

A leaking valve will cause rapid wear and tear on parts

D

Faulty pressure switch will result in pump not starting up

Question 81

Crowning of pulleys are done for :

A

Better belt life

B

Lesser chance of belt running off

C

Less belt slips

D

None of these

Question 82

Which of the following is not true about induction motors ?

A

Rotor of the induction motor cannot run at synchronous speed

B

Motor r.p.m. increases with frequency of input supply

C

Low rotor resistance means high starting torque

D

Direction of rotation of an induction motor can be changed by any two swapping phase leads

Question 83

Which type of valve is used for very fine control of fluid flow ?

A

Butterfly valve

B

Angle valve

C

Ball valve

D

Needle valve

Question 84

Which of the following starters are used for starting a squirrel cage motor ?

A

Star-delta starter

B

Auto-transformer starter

C

Step-down transformer

D

All of these

Question 85

Which of the following is false about D.O.L starters ?

A

No-volt coil disconnects supply to the motor when the supply voltage is lower

B

A thermal overload relay is provided to protect the motor

C

Can be used without backup fuses

D

Due to heavy starting current, their usage is limited beyond a certain motor capacity

Question 86

Which of the following are the features of an ELCB, MCB Circuit breaker ?

A

Over current

B

Short circuit

C

Earth leakage

D

All of these

Question 87

What is cut-off factor of a fuse ?

A

The current at which the fuse element melts

B

Ratio between minimum fusing current and current rating

C

The voltage at which fuse element melts

D

Time taken by a fuse to interrupt the circuit in the event of a fault

Question 88

To what limit of current beyond which Re-wirable fuses are not usually preferred ?

A

200 A

B

350 A

C

500 A

D

1250 A

Question 89

Which of the following relays designed to operate when current falls below a predetermined value ?

A

Electromagnetic relay

B

Current sensing relay

C

Under-current relay

D

Latching relays

Question 90

Which of the following is not a reason of motor running hot ?

A

Open circuit winding

B

Short circuited capacitor

C

Defective capacitor

D

Blown fuse

Question 91

Inside which of the following hydraulic pumps a crescent shaped spacing can be found ?

A

External gear pump

B

Internal gear pump

C

Vane type pump

D

Lobe pump

Question 92

Which of the following is true about temperature sensors ?

A

Its electrical resistance increases with increase in temperature

B

Its electrical resistance decreases with increase in temperature

C

It could be fitted with a balancing coil gauge

D

Its electrical resistance remains unchanged irrespective of temperature changes

Question 93

Which of the following components serves the purpose of retaining the piston down against the seat in balanced condition in a pressure relief valve ?

A

Heavy spring

B

Poppet

C

Adjusting screw

D

Light spring

Question 94

Which of the following is a dependant factor on fluid flow rate of a variable flow control valve ?

A

Pressure difference

B

The size of throttle gap

C

Viscosity of oil

D

All of these

Question 95

Which of the following is not true about pneumatic systems ?

A

FRL assembly also add small quantities of oil into the compressed air systems

B

The expansion of PRV is Pressure Return Valve

C

Pressure switch can restart the compressor motor when the pressure drops below a pre-set value

D

Spool valve is a type of slide valve

Question 96

Which of the following is false about Orifices ?

A

An orifice is the simplest method for controlling fluid flow

B

The orifice is always connected in parallel with the pump

C

Variable orifice is a calibrated needle valve

D

Orifices create a pressure drop

Question 97

Which of the following is not associated with hydraulic actuator speed control ?

A

Meter in speed control

B

Meter out speed control

C

Bleed off speed control

D

Bleed out speed control

Question 98

Which one of the following terms is associated with positive displacement pumps ?

A

Volute casing

B

Semi open impeller

C

Turbine pump

D

Screw rotors

Question 99

Which of the following is not related with pipe joints ?

A

Eccentric reducer

B

Concentric reducer

C

Short nipple

D

Flanged bush

Question 100

Which of the following is not true about pumps ?

A

Rotary pumps don"t need to be primed

B

Increase in fluid temperature causes cavitation

C

Foot valves are non-return valves

D

Self priming devices are connected between discharge pipe and pump

008/2022 - Operator - Kerala Water Authority