4th Class Power Engineering Unit A8: Basic Concepts in Electrotechnology UPDATED QUESTIONS AND CORRECT ANSWERS

4th Class Power Engineering Unit A8: Basic
Concepts in Electrotechnology UPDATED
QUESTIONS AND CORRECT ANSWERS
A typical extra low voltage device would be a:

Select one:

A. Toaster

B. Set of tree lights

C. Door bell

D. Residential lighting - CORRECT ANSWER c



As back EMF decreases the net armature EMF:

Select one:

A. Remains constant

B. Decreases

C. Increases

D. Decreases amount of armature current - CORRECT ANSWER c



Prior to using a voltage meter, what must be known:

Select one:

A. Type of current

B. Type of meter

C. Expected measured value

D. If circuit is open or not - CORRECT ANSWER c



A property of a magnet, is that it will always point in the north direction:

Select one:

A. Freely suspended in the air

B. Charged with electricity

C. It is demagnetized

,D. In the presence of iron filings - CORRECT ANSWER a



An ampere is the _________ of current flow:

Select one:

A. Cause

B. Resistance

C. Measurement

D. Reluctance - CORRECT ANSWER c



Current transformers step down the current rather than the:

Select one:

A. Resistance

B. Voltage

C. Conductance

D. Number of poles - CORRECT ANSWER b



Three phase systems often use__________ to replace three-phase transformers:

Select one:

A. Capacitors

B. Pancake windings

C. Sandwich windings

D. Banks of single-phase - CORRECT ANSWER d



Test meters come in 2 basic types, digital and:

Select one:

A. Pneumatic

B. DMM

C. Analogue

D. LCD - CORRECT ANSWER c

,A moving conductor is at an angle of 90 degrees within the magnetic field:

Select one:

A. Maximum resistance to current flow is attained

B. Current will flow with the least resistance

C. Motor action will be experienced

D. Voltage generated will be at its maximum - CORRECT ANSWER d



The flow of electrons in a uniform direction from atom to atom through a circuit is known as:

Select one:

A. Electromotive force

B. Potential difference

C. A short circuit

D. Current - CORRECT ANSWER d



The magnetic field in a DC machine may be supplied by permanent magnets in small units. Large DC
machines use field poles that are essentially:

Select one:

A. Insulators

B. Resistors

C. Non-magnetic

D. Electromagnets - CORRECT ANSWER d



Three resistors of 170 ohms, 9 ohms, and 570 ohms are connected in series. Determine the total
equivalent resistance:

Select one:

A. 391 ohms

B. 749 ohms

C. 7490 ohms

D. 3910 ohms - CORRECT ANSWER b



The property which determines whether or not a material will be easily magnetized is called:

, Select one:

A. Reaction

B. Conductivity

C. Permeability

D. Magnetism - CORRECT ANSWER c



Ammeters are connected with the negative or black lead connected to the:

Select one:

A. Positive side of the circuit

B. Parallel side of the circuit

C. Negative side of the circuit

D. Switch of the circuit - CORRECT ANSWER c



The strength of the magnetic field produced in a shunt wound generator:

Select one:

A. Is weak

B. Is fairly constant

C. Fluctuates

D. Is regulated by an external AC supply - CORRECT ANSWER b



Three major losses which occur in a transformer are iron losses, copper losses and:

Select one:

A. Cooling losses

B. Heat losses

C. Flux leakage

D. Capacitive losses - CORRECT ANSWER c



A typical low voltage device would include:

Select one:

A. 600V 3 phase motor