Electrical Engineering Multiple Choice Questions (MCQs): 2018

Power System Protection MCQs - Quiz 2 (Circuit Breakers)

Wednesday, March 14, 2018

CIRCUIT BREAKERS

1. In air circuit breakers ___ is used to suppress the arc.
A) Water
B) Air
C) Oil
D) Nitrogen

2. In oil circuit breakers the function of oil is:
A) Cooling
B) Insulation
C) Rust protection
D) Arc suppression

3. The contacts in circuit breakers are made of:
A) Carbon
B) Copper alloy
C) Tungsten
D) Cast iron

4. Which of the following is a routine test in circuit breakers?
A) Contact resistance test
B) Insulation resistance test
C) Timing tests
D) All of above

5. ___ is the voltage that appears across the contacts of the circuit breaker after arc extinction.
A) Surge
B) Recovery
C) Nominal
D) Operating

6. SF6 gas is:
A) Colorless
B) Odorless
C) Not inlfamable
D) All of above

7. The power for shunt trip circuit breaker comes from:
A) Within the breaker
B) External source
C) Either of A or B

8. According to IEC high voltage (HV) circuit breakers are used for ___ voltages.
A) 1 kV or higher
B) 33 kV or higher
C) 72.5 kV or higher
D) None of above

9. Circuit breaker are actuated through ___ mechanism.
A) Hydraulic
B) Pneumatic
C) Spring
D) All of above

10. The trip action in a magnetic circuit breaker is:
A) Instantaneous
B) Delayed
C) Both A & B

Instrumentation and Measurement MCQs - Quiz 3

Thursday, March 8, 2018

1. ___ instruments indicate the instantaneous value of the electrical quantity being measured at a specific time.
A) Absolute instruments
B) Indicating instruments
C) Recording instruments
D) Integrating instruments

2. Which of the following salient features is possessed by an indicating instrument?
A) Controlling device
B) Deflecting device
C) Damping device
D) All of the above

3. A PMMC instrument can be used as flux-meter by:
A) Using a low shunt resistance
B) Using a high series resistance
C) Eliminating the control springs
D) Making control springs of large moment of inertia

4. Which of the following devices may be used for extending the range of instruments?
A) Shunts
B) Multipliers
C) Current transformers
D) Potential transformers
E) All of the above

5. The household energy meter is a/an:
A) Indicating instrument
B) Recording instrument
C) Integrating instrument
D) None of the above

6. The best device to measure the true open circuit EMF of a battery is:
A) Ammeter and a known resistance
B) D.C. voltmeter
C) D.C. potentiometer
D) None of the above

7. For measurement of mutual inductance we can use:
A) Anderson bridge
B) Maxwell's bridge
C) Heaviside bridge
D) Any of the above

8. Direct current can be measured by:
A) DC potentiometer directly
B) DC potentiometer in conjunction with a standard resistance
C) DC potentiometer in conjunction with a volt ratio box
D) None of the above

9. For measuring inductance having high value, we should use:
A) Maxwell's bridge
B) Maxwell Wein’s bridge
C) Hay's bridge
D) Any of the above

10. A voltage of about 200 V can be measured by:
A) DC potentiometer
B) DC potentiometer in conjunction with a volt ratio box
C) DC potentiometer in conjunction with a known resistance
D) None of the above

Instrumentation and Measurement MCQs - Quiz 2

1. Operating torques in analog instruments are:
A) Vibration and balancing
B) Deflecting and damping
C) Deflecting, control and damping
D) Deflecting and control

2. Damping of the Ballistic galvanometer is made small to:
A) Get minimum overshoot
B) Make the system oscillatory
C) Make the system critically damped
D) Get first deflection large

3. Commonly used instruments in power system measurement are ___ type.
A) Induction
B) Moving coil
C) Rectifier
D) Electrostatic

4. In ___ galvanometer the moving part has a large moment of inertia, thus giving it a long oscillation period.
A) Astatic galvanometer
B) Ballistic galvanometer
C) Tangent galvanometer
D) None of the above

5. _____ instruments are used only in laboratories as standardizing instruments.
A) Absolute
B) Indicating
C) Recording
D) Integrating

6. _____ instruments are those which measure the total quantity of electricity delivered in a particular time.
A) Absolute
B) Indicating
C) Recording
D) Integrating

7. ___ are integrating instruments.
A) Ammeters
B) Voltmeters
C) Wattmeters
D) Ampere-hour and watt-hour meters

8. A PMMC instrument can be used as _____ by using a low resistance shunt.
A) Ammeter
B) Voltmeter
C) Flux-meter
D) Ballistic galvanometer

9. Induction type single phase energy meters measure electric energy in:
A) kW
B) Wh
C) kWh
D) VAR

10. For handling greater currents induction a wattmeter is used in conjunction with:
A) Potential transformer
B) Current transformer
C) Power transformer
D) Either of the above

Instrumentation and Measurement MCQs - Quiz 1

Wednesday, March 7, 2018

1. ___ is an instrument which measures the insulation resistance of an electric circuit relative to earth and phase to phase.
A) Tangent galvanometer
B) Megger
C) Current transformer
D) None of the above

2. Resistance can be measured with:
A) Wattmeters
B) Voltmeters
C) Ammeters
D) Ohmmeters and resistance bridges

3. A _____ device prevents the prolonged oscillation of a moving system and enables it to reach its final position in minimum time.
A) Deflecting
B) Controlling
C) Damping
D) Any of the above

4. An induction meter can handle currents up to ___ Amperes.
A) 10
B) 20
C) 50
D) 100

5. The instruments which have cramped scale for larger values, follow:
A) Square law
B) Uniform law
C) Logarithmic law
D) None of the above

6. Insulation resistance measuring instrument is a combination of
A) Motor and generator
B) Generator and ohm meter
C) Generator and voltmeter
D) Generator and ammeter

7. Systematic errors are:
A) Instrumental errors
B) Environmental errors
C) Observational errors
D) All of the above

8. High value of inductance is measured with:
A) Hay’s bridge
B) Whitestone Wein bridge
C) Maxwell Wein bridge
D) Heaviside bridge

9. Standard resistor is made from:
A) Steel
B) Silver
C) Manganin
D) Nichrome

10. Commonly used standard capacitor is:
A) Pherical type
B) Concentric cylindrical type
C) Electrostatic type
D) Multilayer parallel plate type

DC Generators MCQs - Quiz 1

Tuesday, March 6, 2018

1. Which of the following is a part of DC machine?
A) Armature
B) Stator
C) Windings
D) All of above

2. The commutator segments and the armature conductors are connected with:
A) Copper lugs
B) Resistance wires
C) Insulation pads
D) Brazing

3. The field coils of D.C. generator are normally made of:
A) Mica
B) Carbon
C) Cast iron
D) Copper

4. In the commutator:
A) Copper is harder than mica
B) Mica and copper are equally hard
C) Mica is harder than copper
D) None of the above

5. According to Fleming's right-hand rule for finding the direction of induced emf, when middle finger points in the direction of induced emf, then forefinger will point in the direction of
A) Motion of conductor
B) Lines of force
C) Either of the above
D) None of the above

6. In a D.C. generator when the number of poles and the number of armature conductors is fixed, then which winding will give higher emf?
A) Wave winding
B) Lap winding
C) Either of A and B
D) Depends on other features of design

7. Laminations of core are generally made of
A) Cast iron
B) Carbon
C) Silicon steel
D) Stainless steel

8. If B is the flux density, L is the length of conductor and V the velocity of conductor, then induced emf is given by:
A) 2BLV
B) BLV
C) BL/V
D) None of the above

9. In case of a 4 pole DC generator provided with a two layer lap winding with sixteen coils, the pole pitch will be:
A) 4
B) 8
C) 16
D) 32

10. Iron losses in a D.C. machine are independent of variation in:
A) Speed
B) Voltage
C) Load
D) Speed and voltage

Power System Protection MCQs - Quiz 1

Monday, March 5, 2018

1. Insulation resistance of HV circuit breakers is more than ___ mega ohms.
A) 1
B) 10
C) 100
D) 1000

2. Which of the following is the least expensive overcurrent protection for LV system?
A) Isolator
B) Rewireable fuse
C) Oil circuit breaker
D) None of the above

3. The contacts of high voltage breakers used in power system are submerged in oil to:
A) Extinguish the arc
B) Insulate the contacts from switch body
C) Lubricate the contacts
D) None of the above

4. To protect most of the electrical equipment handling low power, the types of relays used are:
A) Thermocouple
B) Electronic and bimetallic
C) Both A & B
D) None of the above

5. The co-efficient of reflection at the open circuited end of a transmission line is:
A) Zero
B) Unity
C) Infinity
D) None of the above

6. A ___ is used to measure the stator winding temperature in a generator.
A) Resistance thermometer
B) Pyrometer
C) Thermocouple
D) Thermometer

7. The under voltage relay can be used for:
A) Generators
B) Busbars
C) Transformers
D) All of the above

8. Which of these devices will receive voltage surge first travelling on the transmission line?
A) Relays
B) Lightning arresters
C) Step down transformer
D) Switchgear

9. Which of the following parameters can be neglected for a short line?
A) Resistance
B) Capacitance
C) Inductance
D) Reactance

10. The relay with inverse time characteristic will operate within ___ sec.
A) 20 to 30
B) 5 to 20
C) 5 to 10
D) None of the above

Cables MCQs - Quiz 1

1. Conduit pipes are normally used to protect _____ cables.
A) Unsheathed
B) Armoured
C) PVC Sheathed
D) All of the above

2. The minimum dielectric stress in a cable is at:
A) Armour
B) Bedding
C) Conductor surface
D) Lead sheath

3. In single core cables armouring is not done to:
A) Make it flexible
B) Avoid excessive sheath losses
C) A & B
D) None of the above

4. Dielectric strength of rubber is nearly:
A) 3 kV/mm
B) 100 kV/mm
C) 30 kV/mm
D) 300 kV/mm

5. Low tension cables are used up to:
A) 250 V
B) 500 V
C) 750 V
D) 1000 V

6. In a cable, the maximum stress under operating conditions is at:
A) insulation layer
B) sheath
C) armour
D) conductor surface

7. High tension cables are used generally up to:
A) 11kV
B) 33kV
C) 66 kV
D) 132 kV

8. The relative permittivity of rubber is between:
A) 2 and 3
B) 5 and 6
C) 8 and 10
D) 12 and 14

9. If the length of a cable is doubled, its capacitance:
A) becomes one-fourth
B) becomes one-half
C) becomes double
D) remains unchanged

10. The surge resistance of cable is around:
A) 5 ohms
B) 20 ohms
C) 40 ohms
D) 100 ohms

Induction Motors MCQs - Quiz 1

Sunday, March 4, 2018

1. In a split phase motor, the running winding should have:
A) high resistance & low inductance
B) low resistance & high inductance
C) high resistance & high inductance
D) low resistance & low inductiance

2. In capacitor start single-phase motors current in the starting winding:
A) leads the voltage
B) lags the voltage
C) is in phase with voltage in running winding
D) none of the above

3. If the capacitor of a single-phase motor is short-circuited, then the motor
A) will start
B) will not start
C) run in reverse direction
D) run at reduced rpm

4. In capacitor start motors, the phase displacement between starting winding and running winding can nearly be ___ degrees.
A) 30
B) 45
C) 60
D) 90

5. Which of these motors will have relatively high starting torque?
A) Salient pole motor
B) Split phase motor
C) Capacitor start motor
D) Shaded pole motor

6. The revolving field in a shaded pole single-phase motor is produced by the use of:
A) shading coils
B) resistor
C) inductor
D) capacitor

7. Which of these motors will have relatively high power factor?
A) Salient pole motor
B) Split phase motor
C) Capacitor run motor
D) Shaded pole motor

8. For high speed and high starting torque, ___ will be selected.
A) Capacitor start motor
B) Capacitor run motor
C) Split phase motor
D) Universal motor

9. Fractional horse power motor has a starting capacitor of ___ uF.
A) 100
B) 200
C) 300
D) 400

10. The motor used in mixer grinder is generally a:
A) Repulsion motor
B) Reluctance motor
C) Hysteresis motor
D) Universal motor

Synchronous Motors MCQs - Quiz 1

Saturday, March 3, 2018

1. A synchronous motor can be started by:
A) Pony motor
B) D.C. compound motor
C) Providing damper winding
D) All of the above

2. A three-phase synchronous motor will have:
A) One slip-ring
B) Two slip-rings
C) Three slip-rings
D) No slip-rings

3. The power developed by a synchronous motor is maximum when the load angle is ___ degrees.
A) 135
B) 90
C) 45
D) 0

4. An ___ synchronous motor can be used as a synchronous capacitor.
A) Under-loaded
B) Under-excited
C) Over-loaded
D) Over-excited

5. Synchronous motors are mostly ___ type machines.
A) Induction
B) Cylindrical
C) Salient pole
D) None of the above

6. Synchronous motors always run at ___ speed.
A) Synchronous
B) More than synchronous
C) Less than synchronous
D) None of the above

7. An over-excited synchronous motor takes ___ current.
A) Lagging
B) Leading
C) Both A & B
D) None of the above

8. The working of a synchronous motor is similar to ___.
A) Transmission of mechancial power by shaft
B) Gear train arrangement
C) Turbine
D) Distribution transformer

9. The back e.m.f. of a synchronous motor depends on
A) Load
B) Load angle
C) Speed
D) None of the above

10. A synchronous motor can operate at ____ power factor.
A) Only unity
B) Only leading
C) Only lagging
D) Leading, lagging and unity

Alternating Current MCQs - Quiz 2

1. ___ is the relation between frequency and time period.
A) T=2f
B) T=f/2
C) T=1/f
D) None of the above

2. The linear distance travelled by a wave during one cyle is called ___.
A) Frequency
B) Wavelength
C) Time period
D) None of the above

3. If L is the inductance of the path through which wave is travelling, C is the capacitance of the path, then velocity of prpagation V = ___
A) 1 / √(LC)
B) 1 / √2(LC)
C) 2 / √(LC)
D) 2 / (LC)

4. Relation between wavelenth λ, frequency f and velocity of propagation V is ___.
A) V = f λ
B) f = V λ
C) λ = f V
D) None of the above

5. Mains frequency for most of Asia, Europe, Australia and Africa is ___.
A) 50 Hz
B) 60 Hz
C) 110 Hz
D) 220 Hz

6. Mains frequency in North America is ___.
A) 50 Hz
B) 60 Hz
C) 110 Hz
D) 220 Hz

7. Mains voltage for most of Asia, Europe, Australia and Africa is ___.
A) 110-127V
B) 220-240V
C) 500V
D) 50V

8. Mains voltage in North America is ___
A) 110-127V
B) 220-240V
C) 500V
D) 50V

9. Too low frequency would result in ___.
A) Flickering
B) High iron losses
C) Both A & B
D) None of the above

10. Too high frequency would result in the problem of ___.
A) Flickering
B) High iron losses
C) Both A & B
D) None of the above

Alternating Current MCQs - Quiz 1

Friday, March 2, 2018

1. The current whose magnitude undergoes a definite cycle of change during a definite interval of time is known as ___
A) Direct current
B) Alternating current
C) Changing current
D) None of the above

2. There are ___ electrical degrees in a cycle.
A) 180
B) 0
C) 360
D) 90

3. The plot of instantaneous values of the varying quantity with time is called ___
A) Waveform
B) Cycle
C) Frequency
D) Phase

4. If Ae is electrical angle, Am is mechanical angle and P is number of poles, then the relation between electrical degrees and mechanical degrees is ___.
A) Ae = 2.P.Am
B) Ae = P.Am
C) Ae = (P/2).Am
D) None of the above

5. If a conductor moves through 360 mechanical degrees in a 2 pole machine, it is supposed to generate ___ electrical degrees.
A) 360
B) 720
C) 180
D) 90

6. If a conductor moves through 360 mechanical degrees in a 4 pole machine, it is supposed to generate ___ electrical degrees.
A) 360
B) 720
C) 180
D) 90

7. In a six pole motor, electrical angle = ___ times mechanical angle.
A) 2
B) 4
C) 6
D) 3

8. The number of cycles per second is called ___.
A) Phase
B) Frequency
C) Amplitude
D) None of the above

9. The unit of frequency is ___
A) Hertz
B) Radian
C) Kelvin
D) None of the above

10. Time period is the time taken to complete ___ cycle
A) One
B) Two
C) Three
D) Four

Electrical Power Transmission MCQs - Quiz 1

1. A power transmission system is a medium through which ___ energy is transferred from generating stations to load centers.
A) Electrical
B) Mechanical
C) Chemical
D) All of above

2. ___ is not used for transmission of electrical power.
A) Steel
B) Aluminum
C) Tungsten
D) Copper

3. Galvanised steel is generally used in ___
A) Earthing
B) Stay wire
C) Structure components
D) All of the above

4. The corona is considerably affected by ___ of conductor.
A) Shape
B) Size
C) Surface condition
D) All of the above

5. A 280 km line falls in category of ___ transmission lines.
A) Short
B) Medium
C) Long
D) None of the above

6. The phenomenon of rise in voltage at the receiving end of the open circuited or lightly loaded line is called ___
A) Faraday effect
B) Maxwell effect
C) Skin effect
D) Ferranti effect

7. The square root of the ratio of line impedance and shunt admittance is called ___ of the line.
A) Inductance
B) Surge impedance
C) Conductance
D) Regulation

8. The conductors in the overhead lines are
A) Stranded
B) Solid
C) Both stranded and solid
D) None of the above

9. _____ transmission lines are higher than 800 kV.
A) MV Medium Voltage
B) HV High Voltage
C) EHV Extra High Voltage
D) UHV Ultra High Voltage

10. High voltage transmission lines use ___
A) suspension insulators
B) pin insulators
C) Both A & B
D) None of the above

Table of contents for our MCQs collection

Thursday, March 1, 2018

Basic Concepts (100 MCQs)
Basic Concepts - Part 1

Alternating Current

Active Components

Passive Components

Transformers (100 MCQs)
Transformers - Part 1
Transformers - Part 2
Transformers - Part 3
Transformers - Part 4
Transformers - Part 5
Transformers - Part 6
Transformers - Part 7
Transformers - Part 8
Transformers - Part 9
Transformers - Part 10

Synchronous Generators (100 MCQs)
Synchronous Generators - Quiz 1

Transformers MCQs - Quiz 5

1. If the secondary of a 1 : 8 transformer is connected to the primary of a 1 : 5 transformer then the total transformation ratio will be ___.
A) 13
B) 5
C) 15
D) 40

2. A transformer having 100 turns in primary winding is given 200 V AC. In order to get 400 V AC at secondary winding the number of turns in secondary winding must be ___.
A) 100
B) 200
C) 300
D) 400

3. Which of the following transformers will be largest in size?
A) 10 kVA, 25 Hz
B) 10 kVA, 50 Hz
C) 10 kVA, 75 Hz
D) 10 kVA, 100 Hz

4. ___ is not a part of transformer.
A) Conservator
B) Breather
C) Exciter
D) Buchholz relay

5. Air Forced cooling is used for transformers up to a rating of ___.
A) 3000 kVA
B) 1500 kVA
C) 1000 kVA
D) 250 kVA

6. Transformer breaths in when load ___.
A) increases
B) decreases
C) remains constant
D) None of the above

7. The noise resulting from vibrations in a transformer is called ___.
A) humming
B) hysteresis
C) magnetization
D) buzzing

8. A distribution transformer has maximum efficiency at ___
A) Full load
B) No load
C) 50 % of full load
D) 80 % of full load

9. The resistance between primary and secondary in a transformer is ___
A) 10 ohms
B) 100 ohms
C) Infinity
D) Zero

10. Transformer oil must be free from ___
A) Gases
B) Moisture
C) Odour
D) Carbon

Transformers MCQs - Quiz 4

Friday, February 23, 2018

1. For performing short circuit test which winding should be short circuited?
A) Low voltage
B) High voltage
C) Secondary
D) Primary

2. Losses occuring during short circuit test are considered ___ losses only because other losses are negligibly small.
A) Iron
B) Copper
C) Hysteresis
D) Eddy current

3. The problem of voltage rise/drop occuring due to increasing/decreasing voltage is handled with the help of ___.
A) Buchholz relay
B) Breather
C) Tap changer
D) None of above

4. Tap changers are used to adjust the ___ of transformer.
A) Temperature
B) Oil level
C) Turns ratio
D) All of above

5. If R is a resistance at secondary side of a transformer and k is transformation ratio, then the equivalent resistance R' as reffered to primary is ___.
A) R/(k²)
B) R/2k
C) 2R/k
D) R²/k

6. Buchholz relay is operared by ___.
A) Current
B) Voltage
C) Gas
D) None of above

7. ___ losses vary highly with load.
A) Copper
B) Iron
C) Hysteresis
D) Eddy current

8. Buchholz relay is used in ___ transformers.
A) Dry type
B) Oil cooled
C) Distribution
D) None of above

9. High frequency transformers use ___ cores.
A) Copper
B) Aluminum
C) Ferrite
D) None of above

10. Step up transformers increase ___
A) Current
B) Voltage
C) Power
D) Frequency

Electrical Power Generation MCQs - Quiz 1

Friday, February 2, 2018

1. What are sources of electrical energy generation?
A) Fossil fuel
B) Nuclear energy
C) Renewable energy
D) All of above

2. Which of these is a renewable energy power plant?
A) Coal power plant
B) Natural gas power plant
C) Hydro power plant
D) All of above

3. Which of following is most environment friendly?
A) Diesel fuel power plant
B) Coal power plant
C) Solar power plant
D) None of above

4. Which of these is a fossil fuel power plant?
A) Geothermal
B) Coal
C) Both A & B
D) None of above

5. Largest source of power generation worldwide is ___.
A) Thermal
B) Hydro
C) Nuclear
D) Solar

6. A steam turbine is used in ___.
A) Wind power plant
B) Solar photovoltaic power plant
C) Coal power plant
D) None of above

7. ___ is used as a fuel in nuclear reactors.
A) Uranium
B) Plutonium
C) Carbon
D) Both A & B

8. ___ isotope of Uranium is used in nuclear power plants.
A) U₂₃₃
B) U₂₃₄
C) U₂₃₅
D) U₂₃₆

9. "Heavy water" is used in ___.
A) Hydel power plants
B) Thermal power plants
C) Steam turbines
D) Nuclear power plants

10. Heavy water is used to ___.
A) Absorb extra heat
B) Slow down neutrons
C) Condense the used steam
D) All of above

Transformers MCQs - Quiz 3

1. Which of the following is a transformer cooling method?
A) ONAN
B) ONAF
C) OFAF
D) All of above

2. Which of the following is a cooling method for dry type transformers?
A) AN (Air Natural)
B) AF (Air Forced)
C) Both A & B
D) None of above

3. Which of the following cooling methods does not require use of energy?
A) OFAF
B) ONAF
C) ONAN
D) OFAN

4. ___ is used to capture any moisture or solid particles in oil.
A) Tank
B) Tap changer
C) Breather
D) Core

5. Buchholz is a type of ___.
A) Steel alloy
B) Relay
C) Tap changer
D) Transformer

6. Neutral of distribution transformer is earthed for ___
A) Safety
B) Balancing of voltages
C) Both A & B
D) None of above

7. Can two transformers be operated in parallel?
A) Yes
B) No

8. What conditions must be met for parallel operation of single phase transformers?
A) Transformation ratio should be same
B) Percentage voltage regulation should be same
C) Polarity should be same
D) All of above

9. What conditions must be met for parallel operation of three phase transformers?
A) Transformation ratio should be same
B) Phase sequence should be same
C) Percentage voltage regulation should be same
D) Phase notation should be same
E) All of above

10. How are the winding of distribution transformers normally connected?
A) Star-Star
B) Delta-Delta
C) Delta-Star
D) Star-Delta

Transformers MCQs - Quiz 2

Thursday, February 1, 2018

1. ___ steel is used in core of a transformer.
A) Cold rolled
B) Hot rolled
C) Grain oriented
D) All of above

2. Efficiency of a transformer depends on ___
A) Load
B) Power factor
C) Both A & B
D) None of above

3. A power transformer is operating at max efficiency if copper losses ___ irons losses
A) Equal to
B) Greater than
C) Smaller than
D) None of above

4. ___ are due to reversal of magnetization in the transformer core.
A) Copper losses
B) Eddy current losses
C) Hysteresis losses
D) None of above

5. Auto-transformer consists of ___
A) One winding
B) Two windings
C) Three windings
D) No windings

6. Three winding transformer consists of ___ winding
A) Primary
B) Secondary
C) Tertiary
D) All of above

7. ___ is the measure of voltage drop from no load to full load.
A) Voltage increment
B) Voltage reduction
C) Loss control
D) Voltage regulation

8. % Voltage regulation = ___ x 100
A) (V_no-load-V_full-load)/2V_full-load
B) (V_no-load+V_full-load)/V_full-load
C) 2(V_no-load-V_full-load)/V_full-load
D) (V_no-load-V_full-load)/V_full-load

9. The value of voltage regulation at capacitive load is ___
A) Zero
B) Infinity
C) Positve
D) Negative

10. Function of oil in transformer tank is ___
A) Cooling
B) Insulation
C) Both A & B
D) None of Above

Transformers MCQs - Quiz 1

Wednesday, January 31, 2018

1. ___ is a device which transforms energy from one circuit to another with a rise or fall in current/voltage.
A) Transformer
B) Motor
C) Generator
D) None of the above

2. Transformer transforms electrical power from primary to secondary winding through ___
A) Magnetic medium
B) Mechanical medium
C) Electrical medium

3. Transformer never changes ___ of alternating current
A) Current
B) Frequency
C) Voltage

4. Transformers are used for ___
A) Increasing or decreasing voltage/current
B) Impedance matching
C) Metering and protection
D) All of above

5. Transfomers work on idea of ___
A) Newton’s law
B) Gauss Theorem
C) Faraday’s law of electromagnetic induction
D) Both B & C

6. What happens when a transformer is operated at no load?
A) It draws a small current called no load current
B) Core is magnetized
C) Core is slightly heated due to losses
D) All of the above

7. Universal transformer equation is ___
A) V1/V2 = N1/N2
B) I1/I2 = N2/N1
C) Both A & B

8. Losses occurring in windings of a transformer are called ___
A) Copper losses
B) Eddy current losses
C) Hysteresis losses

9. Losses occurring in core of a transformer are called ___
A) Copper losses
B) Eddy current losses
C) Hysteresis losses
D) Both B & C

10. Core of a transformer is laminated to reduce ___
A) Copper losses
B) Eddy current losses
C) Hysteresis losses
D) None of above

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