Transformers MCQs - Quiz 4

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

The correct answer is A

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

The correct answer is B

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

The correct answer is C

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

The correct answer is C

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

The correct answer is A

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

The correct answer is C

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

The correct answer is A

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

The correct answer is B

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

The correct answer is C

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

The correct answer is B

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Electrical Power Generation MCQs - Quiz 1

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

The correct answer is D

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

The correct answer is C

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

The correct answer is C

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

The correct answer is B

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

The correct answer is A

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

The correct answer is C

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

The correct answer is D

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

The correct answer is C

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

The correct answer is D

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

The correct answer is B

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Transformers MCQs - Quiz 3

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

The correct answer is D

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

The correct answer is C

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

The correct answer is C

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

The correct answer is C

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

The correct answer is B

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

The correct answer is C

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

The correct answer is A

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

The correct answer is D

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

The correct answer is E

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

The correct answer is C

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Transformers MCQs - Quiz 2

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

The correct answer is D

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

The correct answer is C

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

The correct answer is A

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

The correct answer is C

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

The correct answer is A

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

The correct answer is D

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

The correct answer is D

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

The correct answer is D

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

The correct answer is D

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

The correct answer is C

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