QUESTION 1: MULTIPLE-CHOICE QUESTIONS
Various options are provided as possible answers to the following questions - NSC Electrical Technology Power Systems - Question 1 - 2022 - Paper 1
Question 1
QUESTION 1: MULTIPLE-CHOICE QUESTIONS
Various options are provided as possible answers to the following questions. Choose the answer and write only the letter (A–D)... show full transcript
Worked Solution & Example Answer:QUESTION 1: MULTIPLE-CHOICE QUESTIONS
Various options are provided as possible answers to the following questions - NSC Electrical Technology Power Systems - Question 1 - 2022 - Paper 1
Step 1
1.1 A/N ... is an occurrence when a serious or unexpected dangerous situation occurs that requires immediate attention.
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Answer
A: evacuation procedure
Step 2
1.2 The total opposition against the flow of alternating current in an RLC circuit is the ...
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Answer
B: impedance.
Step 3
1.3 When decreasing frequency to below resonance in a series RLC resonance circuit, the ...
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Answer
C: impedance decreases and the circuit becomes capacitive.
Step 4
1.4 The opposition to AC current flow caused by a capacitor will increase when the ...
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Answer
B: frequency is increased.
Step 5
1.5 An advantage of a three-phase system is that ...
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Answer
D: it is more economical.
Step 6
1.6 Power that is transferred backwards and forwards between the supply and the inductor or capacitor without doing any work is known as ... power.
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Answer
B: reactive.
Step 7
1.7 In an electric power system, a load with a low power factor draws ... current from the supply compared with a load with a high power factor.
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Answer
A: less.
Step 8
1.8 When comparing three-phase transformers to single-phase transformers, a ...
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Answer
C: three-phase transformer can power both single- and three-phase loads.
Step 9
1.9 A Buchholz relay will activate and isolate the transformer from the supply when ...
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Answer
A: a severe fault causes a large amount of gas forming inside the oil of a transformer.
Step 10
1.10 An advantage of a three-phase motor over a single-phase motor is that a three-phase motor ...
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Answer
A: has a lower starting torque.
Step 11
1.11 Refer to the typical speed versus the torque characteristic curve of a three-phase motor. The breakdown torque is ... the full-load torque.
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