EE-prob.88
(time: 30 sec)
A HV DC transmission line supplies a load over a distance of 800 km. The potential
between the positive and negative bus bars at the station is 200 kV. If the loop resistance
of the line is 0.01 ohm/km, what is the maximum power transmitted by this power station?
A. 625 MW
C. 1,250 MW
B. 2,500 MW
D. 10,000 MW
Math-prob.13
(time: 45 sec)
The sum of the digits of a number of three digits is 15. If the digits in the hundred’s
and tens’ places are interchanged, the number is increased by 360. The units’ digit is ¼
of the sum of the hundreds’ and tens’ places. What is the number?
Ans: 483
EE-prob.94
(time: 30 sec)
A 10 ohm resistance and a 20 ohm resistance and connected in parallel. Another
5 ohm resistance is connected in series with the two. A battery of 48 Volts with an internal
resistance of 0.2 ohm supplies the parallel-series network. What current passes through
the 20 ohm resistance?
Ans: 1.35 Amp
PEC-3 (E)
A compartment or chamber to which one or more air ducts are connected and that
forms part of the air distribution system.
Ans. Plenum
Math-prob.49
(time: 60 sec)
A 220 Volt, 6 hp motor has an efficiency of 74.6%. if power cost is Php0.18 per
kW-hr for the 1st 50 kW-hr, Php0.17 per kW-hr for the next 50 kW-hr, and Php0.16 per
kW-hr for the third 50 kW-hr, and so on until a minimum of Php0.06 per kW-hr is reached.
How much does it cost to run this motor continuously for 8 days?
Ans: Php96.60
EE-prob.89
(time: 30 sec)
The effective value of e = 100 + A sin t Volt is known to be 103.1 Volts. What is
the amplitude A of the sine term?
Ans: 35.485
EE-prob.105
(time: 45 sec)
A 1-phase transformer 75 kVA, 60 Hz, 8000/240 Volts is given a short circuit test,
a 440 Volts is impressed in the primary which then draws rated current at 1125 Watts.
Compute for the percent impedance and percent reactance of the transformer.
Ans: %Z=5.5%, %X=5.292%
PEC-8 (A)
For dwelling units, the computed floor area shall NOT include _____.
I. Carports
III. Bathrooms
II. Garages
IV. Open porches
A. II and IV
C. I, II and III
B. I, III and IV
D. I, II, III and IV
Math-prob.56
PEC 2.10.1.3(a)
(time: 30 sec)
In poker game consisting of 5 cards, what is the probability of holding 2 Aces and
2 Queens?
Ans. 33/54145 = 0.000609474
EE-prob.124
(time: 30 sec)
A 132 KV line, three phase system delivers 70.71 MVA of a balanced delta
connected load of p.f. = 70.71%. Determine the reactance necessary to attain unity p.f.
Ans: 1045.46 ohms
ESAS-prob.70
(time: 5 sec)
It refers to a generating unit that assists in frequency control by providing automatic
primary and/or secondary frequency response.
Ans: Frequency Regulating Reserve
EE-prob.119
(time: 10 sec)
A 3-phase, 60 Hz, induction motor has full load speed of 1155 rpm. For this motor,
the speed of stator field with respect for revolving rotor structure will be ?
A. 1,155 rpm
C. 1,200 rpm
B. 1,440 rpm
D. 45 rpm
Math-prob.74
(time: 20 sec)
A rope is fastened from the tip of a 15 m electric post to the foot of a 10 m pole.
Another is fastened from the tip of the 10 m pole to the foot of 15 m electric post. If the
two ropes are taut, how far above the ground will they intersect?
Ans: 6 meters
EE-prob.126
(time: 30 sec)
A 25 kVA, single phase transformer the core loss and full load copper loss are 320
W and 380 W respectively. What is the efficiency at half load and 86.6% power factor?
Ans: 96.308%
PEC-9 (D-10sec)
According to the P.E.C. high voltage service-entrance conductors are protected by
a circuit breaker if it has ____ the ampacity of the conductor for its trip setting (short
circuit protection).
PEC 2.80.8.9
A. 2 times
C. 6 times
B. 4 times
D. 8 times