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What is the most efficient method of utilizing the heat from the sun?
Flat plate collector
What might prevent the voltage from building up in a self-excited four-pole AC generator after rewinding?
The field winding circuit is open
Why is laminated iron used in AC magnetic circuits?
To reduce eddy current loss
Which gaseous fuel has the highest heating value?
Butane gas
What factors affect the overall efficiency of a lighting installation?
All of the above
What is the name for a P-type semiconductor?
Acceptor
Which color television transmission standard has been adopted by the Philippines?
NTSC
What is an effective remover of dust and carbon particles from fuel gas in a power plant?
Dust scrubber
Which loads cause a phase shift between voltage and current vectors?
Electric flat irons
What is a characteristic of the double-bus double-breaker scheme?
It gives more flexibility.
What is the normal secondary circuit current of a current transformer?
5 A
In a stranded conductor, what do you call the strand at the center?
King wire
What electrode in a junction transistor corresponds to the cathode in a vacuum tube?
Emitter
Which term is related to magnetic flux?
Gauss
What is the connection type of the armature winding in a shunt motor?
Parallel
What is a pure semiconductor without doping called?
Intrinsic
What combination does an SCR feature?
Rectifier and transistor.
What type of fuel has the largest known reserves for energy extraction?
Coal
What transformer provides a continuously variable output voltage?
Variac
What is the common type of conductor used for overhead transmission lines?
ACSR
Ohm's law does NOT apply to which type of circuit?
Electronic circuit
What is the maximum distance allowed for a grounding electrode conductor?
Connected to an electrode encased by at least 50 mm of concrete.
What type of alert is raised for a tropical storm in the Philippine Grid Code?
Yellow alert
What is the result of a three phase short circuit of an alternator?
Maximum.
How is a galvanometer converted into an ammeter?
By placing a low resistance in series.
What is the total power input in back-to-back tests for a transformer with equal core-losses?
Two.
What type of motor is used in electric toys?
Shaded-pole motor.
What is the concentration of independent equations containing emfs, resistances, and currents in any circuit?
Branches minus 1.
Which instrument is commonly used to check the alignment of a motor shaft?
Dial indicator.
Which equipment design considers power loss the most?
Transmission line.
What is not included in technical performance standards for electrical distribution?
Collection efficiency.
Which is a primary disadvantage of FM over AM?
Higher cost and complexity.
How to adjust the power of an alternator?
Adjust the field current.
What is the surge impedance in a negligible resistance transmission line?
Square root of LC.
What happens to the short circuit current?
It lessens.
What type of testing is used to determine copper loss in a transformer?
Short circuit.
When voltage is increased n times, how does conductor size change for constant efficiency?
Reduce to 1/n^2 times.
How does power transmission capacity relate to voltage?
Proportional to the square of voltage.
What is the purpose of undervoltage relays?
Motor protection.
Which type of fault involves only positive sequence impedance?
Line to ground.
What is the primary advantage of FM over AM?
Noise immunity.
What does a fuse primarily protect against?
Excessive currents.
Which DC motor requires a load to operate?
Series.
When heating is the sole purpose of AC, based on what should conductor selection be made?
RMS value.
What type of relay responds to differences between incoming and outgoing electrical quantities?
Differential.
Which does not affect the speed of a DC motor?
Thickness of the commutator bars.
What statement is correct about resistance?
Resistance of a conductor is the hindrance it presents against current flow.
What is the ampacity of a feeder conductor?
The sum of the full-load motor currents plus the currents of other loads.
What is the best conductor of electricity?
China clay.
How is generator 'motorizing' prevented?
By using a reverse power relay.
Which is not included in the technical performance standards for Philippine Distribution Code?
Plant efficiency.
Which kind of outages is included in the reliability standard indices calculation?
Outages that occur on primary lines.
What happens to resistance when length increases?
It increases.
What is the required distance for receptacle outlets in a dwelling unit?
No point is farther than 1,800 mm from an outlet.
What does specific resistance depend on?
Material of the conductor and its area and length.
Which is not a consideration for surge arresters?
Arrester class.
What type of power plant is best suited for peak load?
Peaking power plant.
Under very slow deformation at high temperature, this phenomenon occurs:
Creep.
Which programming language is suited for scientific applications?
FORTRAN.
What happens when the load shared by an alternator increases?
Strengthen the field excitation.
What will be the fuel of the future after hydrocarbon depletion?
Deuterium.
For ACSR conductors, what is the formula for the total number of strands?
3n^2 - 3n + 1.
For the efficiency of constant transmission, what change occurs when voltage increases?
Reduce to 1/n^2 times.
How does an increase in frequency affect the transmission line?
The shunt reactance increases.
What results from skin effect?
Increase in AC resistance.
What occurs in overhead lines due to earth presence?
Capacitance increases.
What phenomenon involves differences in current flow density?
Skin effect.
Which is a factor in electrical power design regarding voltage regulation?
Transformer.
What is not considered when selecting the fuse rating?
Branch fault-current.
What principle is fiber-optic cable operation based on?
Reflection.
What does current do as impedance decreases?
Increase.
If the fault in the circuit is reversed, how does it affect current flow?
It reverses the direction of the current flow.
For a very large current through a ring-shaped coil, how is the magnetic induction affected?
It increases.
What happens to the power consumed if voltage across a resistor is reduced by 50%?
It will reduce by 75%.
What happens to the size of a conductor if voltage is increased for constant transmission efficiency?
Reduce to 1/n^2 times.
The phenomenon where two bodies in thermal equilibrium with a third are also in equilibrium with each other is known as:
Zeroth law of thermodynamics.
Define a circuit conductors between the final overcurrent device and the outlet(s).
Branch circuit.
When released from a height h, what is the final velocity of the mass?
v = √2gh.
What conducting connection to earth is called?
Grounded.
What is the essential part of a dam that releases excess flow?
Spillway.
Which permit is needed before any electrical installation work?
Electrical permit.
What does Sec. 34 of Art. IV of RA 7920 specify?
Preparations of plans, supervision of installation.
Which in this context refers to CHED?
Commission.
What occurs when a storm makes a landfall?
Yellow alert.
What are the partially protected locations under canopies called?
Damp location.
What refers to installations underground or in direct contact with earth?
Wet location.
Which location is temporarily subject to dampness?
Damp.
What cannot be a rule in PEC?
Manufacturing Rule.
What is the compact arrangement of switching devices called?
Switchgear.
The term for the electrical connection to earth is:
Ground.
When one experiences an overload condition, how many causes might they have?
At least one.
Business Value equals?
Tangible Elements + Intangible Elements.
Which of these is NOT a tangible element?
Trademarks.
The correct project cycle involves what sequence?
Initiating - Planning - Executing - Closing.
What technique uses vertical bars against a calendar?
Gantt chart.
In a wire with current running north, which direction does the magnetic field go?
East.
What principle states that the sum of emfs around a closed loop equals zero?
Conservation of energy.
What relates to the electric field?
The force acting on a test charge.
What indicates current density moves in a certain wire?
The current density points left and the electric field points right.
Which is the effective resistance of the conductor is increased by?
Both skin effect and proximity effect.
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