Quiz Questions

Question 1 1 Marks

How many diodes are required for making a
bridge rectifier circuit?

A

One

B

Two

C

Four

D

Three

Question 2 1 Marks

Which electronic component is the voltage regulator?

A

Zener diode

B

Transistor

C

Triac

D

Diac

Question 3 1 Marks

What is the unit of inductance?

A

Ohm

B

Henry

C

Farad

D

Ampere

Question 4 1 Marks

Which application uses the digital
ICs?

A

Amplifier

B

Logic gates

C

Tuned circuits

D

Voltage regulator

Question 5 1 Marks

What is the reverse break down voltage range of zener diode?

A

0.1 to 0.5 volt

B

0.5 to 1 volt

C

3 to 18 volt

D

1 to 3 volt

Question 6 1 Marks

How the maximum reverse voltage across the diode is termed in reverse biased condition?

A

Diode voltage

B

Ripple frequency

C

Peak inverse voltage

D

Peak rectification voltage

Question 7 1 Marks

Which semiconductor material is used to make diodes?

A

Steel

B

Silicon

C

Copper

D

Aluminium

Question 8 1 Marks

What is the process involved for converting AC to DC power supply?

A

Inversion

B

Regulation

C

Convection

D

Rectification

Question 9 1 Marks

How many terminals are there in a Silicon Controlled Rectifier (SCR)?

A

One

B

Two

C

Four

D

Three

Question 10 1 Marks

Which component is used as a switching device in electronic circuit?

A

SCR

B

Diode

C

Capacitor

D

Zener diode

Question 11 1 Marks

What are the passive components used in
electronic circuits?

A

Resistors, capacitors and inductors

B

Transformers and semiconductors

C

Semi conductors and transistors

D

Transistors, diodes and SCRs

Question 12 1 Marks

Which material is used for making zener diode?

A

Lead

B

Silicon

C

Titanium

D

Platinum

Question 13 1 Marks

Which type of diode is used for communication circuits?

A

Signal diode

B

Zener diode

C

Rectifier diode

D

Switching diode

Question 14 1 Marks

What is the name of electronic
circuit?

A

Bridge rectifier

B

Half wave rectifier

C

Full wave rectifier

D

Quarter wave rectifier

Question 15 1 Marks

What is the name of active component used in electronic circuit?

A

Transistor

B

TRIAC

C

DIAC

D

SCR

Question 16 1 Marks

Which meter indicates the true power directly in an electrical circuit?

A

Ammeter

B

Ohm meter

C

Watt meter

D

Volt meter

Question 17 1 Marks

What is the rotor speed with respect to stator field speed in an induction motor?

A

Less than the stator speed

B

More than the stator speed

C

Equal to the stator speed

D

More than the fly wheel

Question 18 1 Marks

Which material is used to avoid oxidation between aluminium conductor and the terminal?

A

Petrol

B

Grease

C

Shellac

D

Kerosene

Question 19 1 Marks

Which winding has more inductance in refrigerator compressor motor?

A

Run

B

Start

C

Common

D

Start and common

Question 20 1 Marks

Which joint is made in either single or multi - strand conductors?

A

Rat tail joint

B

Scarfed joint

C

Britannia joint

D

Western union joint

Question 21 1 Marks

Which type of rotor is used in split phase induction motor?

A

Wound coil

B

Eccentric

C

Squirrel cage

D

Permanent magnet

Question 22 1 Marks

Which type of conductor is used for bus bars?

A

Solid conductor

B

Thermal conductor

C

Stranded conductor

D

Standard conductor

Question 23 1 Marks

Which law relates to voltage, current and resistance in an electrical circuit?

A

Ohm s law

B

Lenz s law

C

Newton s law

D

Faraday s law

Question 24 1 Marks

What is the unit of electric current?

A

Ampere

B

Farad

C

Ohm

D

Volt

Question 25 1 Marks

Which tool is used for skinning the insulation of cables and cleaning the wire surface?

A

Hacksaw

B

Firmer chisel

C

Electrician's knife

D

Combination pliers

Question 26 1 Marks

What is the unit of capacitance?

A

Volt

B

Ampere

C

Farad

D

Coulomb

Question 27 1 Marks

What is the supply voltage if a current of 2 ampere flows through 10 Ohm resistor in a circuit?

A

20 Volt

B

45 Volt

C

55 Volt

D

65 Volt

Question 28 1 Marks

What is the total resistance if two resistors R1 and R2 are connected in series?

A

(R1 - R2) Ohms

B

(R1 + R2) Ohms

C

(R1 x R2) Ohms

D

(R1 / R2) Ohms

Question 29 1 Marks

What is the unit of electrical energy?

A

Volt

B

Watt

C

Ampere

D

Kilo watt hour

Question 30 1 Marks

Which material is used for making disc in energy meter?

A

Aluminium

B

Copper

C

Brass

D

Zinc

Question 31 1 Marks

Which power supply has the fixed polarity?

A

Direct current

B

Signal voltage

C

Signal ripples

D

Alternating current

Question 32 1 Marks

What is the condition of compressor motor if Ohm meter reads infinity across common and start terminals?

A

Running winding open

B

Starting winding open

C

Starting winding shorted

D

Running winding shorted

Question 33 1 Marks

Which is the common terminal while Ohm meter reads AB = 10 Ohm, AC = 15 Ohm and BC = 25 Ohm if the motor terminals are A, B and C?

A

Terminal A

B

Terminal B

C

Terminal C

D

Earth Terminal

Question 34 1 Marks

What is the maximum capacity of 3 phase squirrel cage induction motor used with direct on line (DOL) starter?

A

5 HP

B

10 HP

C

15 HP

D

20 HP

Question 35 1 Marks

What is the effect of pouring water on electrodes resistance in earth pit?

A

Decreases

B

Increases

C

Equalises

D

Remains same

Question 36 1 Marks

What is the load resistance in an electrical circuit, if current, I = 2 amp and supply, V = 10 volt?

A

2 Ohms

B

3 Ohms

C

4 Ohms

D

5 Ohms

Question 37 1 Marks

Which winding has low resistance in resistance start induction run motor?

A

Running winding

B

Starting winding

C

Auxiliary winding

D

Common winding

Question 38 1 Marks

Which type of 1-? motor has high starting torque?

A

Permanent capacitor

B

Resistance start induction run

C

Capacitor start and capacitor run

D

Induction start and induction run

Question 39 1 Marks

Which property limits the flow of electrons in an electrical circuit?

A

Voltage

B

Current

C

Resistance

D

Conductance

Question 40 1 Marks

How electrons flow in a battery circuit?

A

Phase to earth

B

Phase to neutral

C

Positive to negative polarity

D

Negative polarity to positive polarity

Question 41 1 Marks

What is the boiling point of pure water in centigrade scale?

A

212 Degree Centigrade

B

100 Degree Centigrade

C

32 Degree Centigrade

D

0 Degree Centigrade

Question 42 1 Marks

What is the barometer reading at sea level in Hg column?

A

760 mm

B

750 mm

C

740 mm

D

730 mm

Question 43 1 Marks

How the level of heat in a substance is
expressed?

A

Micron

B

Pressure

C

Humidity

D

Temperature

Question 44 1 Marks

What is the purpose of accumulator in a refrigerator?

A

Improves oil circulation

B

Prevents surging of refrigerant

C

Avoids hunting of refrigerant

D

Prevents liquid flood back to compressor

Question 45 1 Marks

Which factors produce work?

A

Force and distance

B

Time and distance

C

Force and power

D

Force and time

Question 46 1 Marks

What is the equivalent absolute scale for centigrade?

A

Kelvin

B

Celsius

C

Rankine

D

Fahrenheit

Question 47 1 Marks

Which law is related to the constant PV at constant T?

A

Boyles law

B

Charles s law

C

Pascal s law

D

Renaults law

Question 48 1 Marks

What is effect of compression process on refrigerant vapour?

A

Heat the vapour below saturation

B

Cool the vapour above saturation

C

Increase the pressure and temperature

D

Decrease the pressure and temperature

Question 49 1 Marks

What is the melting temperature of silver
brazing rod?

A

1120 Degree F

B

1200 Degree F

C

1250 Degree F

D

1300 Degree F

Question 50 1 Marks

What is the rate of doing work?

A

Duty

B

Force

C

Power

D

Velocity

Question 51 1 Marks

Which two components do the compressor function in vapour absorption system?

A

Generator and absorber

B

Generator and separator

C

Generator and condenser

D

Generator and evaporator

Question 52 1 Marks

Which refrigeration system works on
directly by the heat energy?

A

Jet refrigeration

B

Mechanical refrigeration

C

Vapour absorption refrigeration

D

Vapour compression refrigeration

Question 53 1 Marks

What is top dead centre in reciprocating compressor cylinder?

A

The piston moves down from the point of cylinder

B

The piston moves up from the point of cylinder

C

The piston stops in cylinder at bottom

D

The piston starts in cylinder at bottom

Question 54 1 Marks

Which components maintain the pressure difference in RAC system?

A

Condenser and filter

B

Evaporator and motor

C

Receiver and condenser

D

Compressor and expansion device

Question 55 1 Marks

Which instrument is used to measure atmospheric pressure?

A

Hygrometer

B

Hydrometer

C

Manometer

D

Barometer

Question 56 1 Marks

What is the unit of heat in M.K.S system?

A

B.T.U (British thermal unit)

B

K.Cal (Kilo Calorie)

C

KV (Kilo Volt)

D

K.W (Kilo Watt)

Question 57 1 Marks

Which method is used to connect the swaged joint in copper tubes?

A

TIG welding

B

Silver brazing

C

Lead soldering

D

Fusion welding

Question 58 1 Marks

What is the absolute zero temperature in
degree centigrade?

A

0 Degree Centigrade

B

100 Degree Centigrade

C

-273 Degree Centigrade

D

212 Degree Centigrade

Question 59 1 Marks

Which component controls the thermostat and defrost heater in frost free refrigerator?

A

Thermoheater

B

Defrost timer

C

Relay

D

OLP

Question 60 1 Marks

What is the atmospheric pressure at sea
level?

A

1.033 kg/cm2

B

1.3 Kg/cm2

C

1.5 Kg/cm2

D

1.6 Kg/cm2

Question 61 1 Marks

Why there is no frosting at the bottom only in plate coil evaporator used with refrigerator?

A

Shortage of refrigerant

B

Oil present in the coil

C

Excess of refrigerant

D

Liquid in the coil

Question 62 1 Marks

What is the remedy for broken bimetal thermo in a frost free refrigerator?

A

Repair the bimetal thermo

B

Reuse the bimetal thermo

C

Replace the bimetal thermo

D

Readjust the bimetal thermo

Question 63 1 Marks

Which device meters the amount of refrigerant entering the evaporator in window AC?

A

Accumulator

B

Capillary tube

C

Heat exchanger

D

Finned tube condenser

Question 64 1 Marks

Which cooling medium is used to condense the refrigerant vapour in plate and tube condenser?

A

Natural Air

B

Forced Air

C

Water

D

Brine solution

Question 65 1 Marks

Which gas is used to flush out the coils of air cooled condenser?

A

Dry nitrogen

B

Pure dry air

C

Oxygen

D

kaksr

Question 66 1 Marks

Why frost accumulates in window AC evaporator?

A

Over charge of refrigerant

B

Less charge of refrigerant

C

Capillary chocking

D

Air filter blocked

Question 67 1 Marks

What is the physical state of refrigerant at the outlet of condenser in vapour compression cycle?

A

High pressure vapour

B

High pressure liquid

C

Low pressure liquid

D

Low pressure vapour

Question 68 1 Marks

What is the physical change of refrigerant in evaporator?

A

Solid to liquid

B

Vapour to solid

C

Liquid to vapour

D

Vapour to liquid

Question 69 1 Marks

Which colour is used for painting condenser coil?

A

Green

B

Black

C

Blue

D

Red

Question 70 1 Marks

Which type of defrosting method is used in frost free refrigerator?

A

Hot water defrosting

B

Manual defrosting

C

Hot gas defrosting

D

Electric defrosting

Question 71 1 Marks

Which type of evaporator is used in house hold refrigerator?

A

Plate evaporator

B

Tube in tube evaporator

C

Shell and coil evaporator

D

Shell and tube evaporator

Question 72 1 Marks

What is the reason for frost accumulation in
between fins and tubes of evaporator in frost free
refrigerator?

A

Under charge of refrigerant

B

Over charge of refrigerant

C

Defective fan motor

D

Defective timer

Question 73 1 Marks

Which evaporator is known as extended surface evaporator?

A

Evaporator tubes

B

Finned evaporator

C

Bare tube evaporator

D

Coiled stake evaporator

Question 74 1 Marks

Which type of drier filter is suitable for HFC refrigerants?

A

Molecular sieve type

B

Activated alumina

C

Activated carbon

D

Silica gel

Question 75 1 Marks

What is the advantage of using capillary tube as an expansion device?

A

Temperature balancing is easy

B

Pressure balancing is easy

C

Volume balancing is easy

D

Complicate design

Question 76 1 Marks

Which type of expansion device is used in frost free refrigerator?

A

Float valve

B

Capillary tube

C

Automatic expansion valve

D

Thermostatic expansion valve

Question 77 1 Marks

Why evaporator of air conditioner has more fins per inch?

A

Increase the air contact

B

Increase the water dripping

C

Decrease the air circulation

D

Produce more ice

Question 78 1 Marks

What is the use of dehydrator?

A

Absorb oil

B

Absorb heat

C

Absorb refrigerant

D

Absorb moisture

Question 79 1 Marks

Which application uses the capillary tube expansion device?

A

Domestic RAC units

B

Industrial ice plants

C

Commercial AC plants

D

Hospital IAQ systems

Question 80 1 Marks

Which component is connected in series with bimetal thermo in a frost free refrigerator?

A

Blower

B

Door switch

C

Cabinet bulb

D

Defrost heater

Question 81 1 Marks

What is the type of condenser used in direct cool refrigerator?

A

Fin and tube

B

Shell and tube

C

Wire mesh

D

Tube in tube

Question 82 1 Marks

Where the dehydrator is installed in a refrigeration system?

A

Discharge line

B

Capillary line

C

Suction line

D

Liquid line

Question 83 1 Marks

Which gas is used for flushing blocked capillary tube?

A

Moist air

B

Hydrogen

C

Dry nitrogen

D

Aqua ammonia

Question 84 1 Marks

What is the purpose of chemical spraying on finned condenser?

A

Flush out the condenser tubes

B

Remove the rust on the fins

C

Blow the dust from the fins

D

Correct the bends in fins

Question 85 1 Marks

Which type of insulation material is used in modern refrigerators?

A

Saw dust

B

Glass wool

C

Thermocole

D

Poly urethane foam

Question 86 1 Marks

What are the causes for blockage in
capillary tube?

A

Non condensable gases

B

Moisture and wax from oil

C

Solid particles

D

Over charging of refrigerant

Question 87 1 Marks

What is the desiccant used in dehydrator of hydrocarbon charged RAC unit?

A

Silica gel

B

Ammonia

C

Sulphur dioxide

D

Calcium chloride

Question 88 1 Marks

How much minimum gap is left on either side of the refrigerator from the wall during installation?

A

5 cm

B

10 cm

C

15 cm

D

25 cm

Question 89 1 Marks

Which expansion valve is suitable for constant load operation?

A

King valve

B

Relief valve

C

Low side float valve

D

Automatic expansion valve

Question 90 1 Marks

Why the supply air throw is decreased in window AC?

A

Normal RPM of fan motor

B

Clean air filter

C

Refrigerant leaks

D

Frost blocks air circulation

Question 91 1 Marks

How pressure drop is achieved in capillary tube of refrigeration cycle?

A

The friction between refrigerant and tube

B

The friction between refrigerant and oil

C

The friction between piston and cylinder

D

The friction between belt and pulley

Question 92 1 Marks

Why the capillary tube is preferred as an
expansion device?

A

No system pressure equalising

B

Inexpensive and has no moving parts

C

Expensive and more moving parts

D

Periodical servicing is required

Question 93 1 Marks

What is the remedy for defective heating element in a frost free refrigerator?

A

Repair heater

B

Readjust the heater

C

Replace heater and bimetal thermo

D

Reuse the heater and over load protector

Question 94 1 Marks

What is the reason for no cooling in a frost
free refrigerator?

A

Defective fan motor

B

Open door switch

C

High watt Cabinet bulb

D

Defective timer

Question 95 1 Marks

Which is the constant reference for the working of AEV?

A

Oil temperature

B

Suction pressure

C

Volume expansion

D

Discharge pressure

Question 96 1 Marks

Which type of condenser is used in window Air conditioner?

A

Natural convection

B

Forced convection

C

Water cooled

D

Evaporative

Question 97 1 Marks

Which is the constant operating condition of TEV?

A

Super heat at suction line point

B

Evaporator pressure at its inlet

C

Enthalpy at the evaporator outlet

D

Entropy at the condenser outlet

Question 98 1 Marks

What is the process of accumulation of ice on the surface of evaporator?

A

Frosting

B

Defrosting

C

Evacuating

D

Melting of frost

Question 99 1 Marks

What is the effect of pressure drop at the inlet of the evaporator?

A

Flashing of liquid refrigerant

B

Freezing of liquid refrigerant

C

Freezing of liquid

D

Boiling of oil

Question 100 1 Marks

Which component is connected in series with defrost heater in a frost free refrigerator?

A

Door switch

B

Cabinet bulb

C

Bimetal thermo

D

Heating element

How many diodes are required for making a bridge rectifier circuit?

Which electronic component is the voltage regulator?

What is the unit of inductance?

Which application uses the digital ICs?

What is the reverse break down voltage range of zener diode?

How the maximum reverse voltage across the diode is termed in reverse biased condition?

Which semiconductor material is used to make diodes?

What is the process involved for converting AC to DC power supply?

How many terminals are there in a Silicon Controlled Rectifier (SCR)?

Which component is used as a switching device in electronic circuit?

What are the passive components used in electronic circuits?

Which material is used for making zener diode?

Which type of diode is used for communication circuits?

What is the name of electronic circuit?

What is the name of active component used in electronic circuit?

Which meter indicates the true power directly in an electrical circuit?

What is the rotor speed with respect to stator field speed in an induction motor?

Which material is used to avoid oxidation between aluminium conductor and the terminal?

Which winding has more inductance in refrigerator compressor motor?

Which joint is made in either single or multi - strand conductors?

Which type of rotor is used in split phase induction motor?

Which type of conductor is used for bus bars?

Which law relates to voltage, current and resistance in an electrical circuit?

What is the unit of electric current?

Which tool is used for skinning the insulation of cables and cleaning the wire surface?

What is the unit of capacitance?

What is the supply voltage if a current of 2 ampere flows through 10 Ohm resistor in a circuit?

What is the total resistance if two resistors R1 and R2 are connected in series?

What is the unit of electrical energy?

Which material is used for making disc in energy meter?

Which power supply has the fixed polarity?

What is the condition of compressor motor if Ohm meter reads infinity across common and start terminals?

Which is the common terminal while Ohm meter reads AB = 10 Ohm, AC = 15 Ohm and BC = 25 Ohm if the motor terminals are A, B and C?

What is the maximum capacity of 3 phase squirrel cage induction motor used with direct on line (DOL) starter?

What is the effect of pouring water on electrodes resistance in earth pit?

What is the load resistance in an electrical circuit, if current, I = 2 amp and supply, V = 10 volt?

Which winding has low resistance in resistance start induction run motor?

Which type of 1-? motor has high starting torque?

Which property limits the flow of electrons in an electrical circuit?

How electrons flow in a battery circuit?

What is the boiling point of pure water in centigrade scale?

What is the barometer reading at sea level in Hg column?

How the level of heat in a substance is expressed?

What is the purpose of accumulator in a refrigerator?

Which factors produce work?

What is the equivalent absolute scale for centigrade?

Which law is related to the constant PV at constant T?

What is effect of compression process on refrigerant vapour?

What is the melting temperature of silver brazing rod?

What is the rate of doing work?

Which two components do the compressor function in vapour absorption system?

Which refrigeration system works on directly by the heat energy?

What is top dead centre in reciprocating compressor cylinder?

Which components maintain the pressure difference in RAC system?

Which instrument is used to measure atmospheric pressure?

What is the unit of heat in M.K.S system?

Which method is used to connect the swaged joint in copper tubes?

What is the absolute zero temperature in degree centigrade?

Which component controls the thermostat and defrost heater in frost free refrigerator?

What is the atmospheric pressure at sea level?

Why there is no frosting at the bottom only in plate coil evaporator used with refrigerator?

What is the remedy for broken bimetal thermo in a frost free refrigerator?

Which device meters the amount of refrigerant entering the evaporator in window AC?

Which cooling medium is used to condense the refrigerant vapour in plate and tube condenser?

Which gas is used to flush out the coils of air cooled condenser?

Why frost accumulates in window AC evaporator?

What is the physical state of refrigerant at the outlet of condenser in vapour compression cycle?

What is the physical change of refrigerant in evaporator?

Which colour is used for painting condenser coil?

Which type of defrosting method is used in frost free refrigerator?

Which type of evaporator is used in house hold refrigerator?

What is the reason for frost accumulation in between fins and tubes of evaporator in frost free refrigerator?

Which evaporator is known as extended surface evaporator?

Which type of drier filter is suitable for HFC refrigerants?

What is the advantage of using capillary tube as an expansion device?

Which type of expansion device is used in frost free refrigerator?

Why evaporator of air conditioner has more fins per inch?

What is the use of dehydrator?

Which application uses the capillary tube expansion device?

How many diodes are required for making a
bridge rectifier circuit?

Which application uses the digital
ICs?

What are the passive components used in
electronic circuits?

What is the name of electronic
circuit?

How the level of heat in a substance is
expressed?

What is the melting temperature of silver
brazing rod?

Which refrigeration system works on
directly by the heat energy?

What is the absolute zero temperature in
degree centigrade?

What is the atmospheric pressure at sea
level?

What is the reason for frost accumulation in
between fins and tubes of evaporator in frost free
refrigerator?

What are the causes for blockage in
capillary tube?

Why the capillary tube is preferred as an
expansion device?

What is the reason for no cooling in a frost
free refrigerator?