SERIES 4 309.

Unlike microprocessors, micro controllers make use

of batteries because they have
301.Feedback in an amplifier always helps to
A. High power dissipation
A. Control its output
B. Low power consumption
B. Increase its gain
C. Low voltage consumption
C. Decrease its input impedance
D. Low current consumption
D. Stabilize its gain
Ans. B
Ans. A
310.Ripple factor of a bridge rectifier Is
302.The internal resistance of a saturated Weston cell is
A. 0.5
of the order of
B. l
A. A few hundred ohms
C. 2
B. Negligible
D. 0.75
C. Infinite
Ans. A
D. Thousand ohms
311.Which of the following is NOT a purpose of
Ans. A
Disturbance Monitoring?
303.If two or more interrupts occur during execution,
A. Model validation
the sequence of appearance of interrupt’s
B. Disturbance investigation
Is called
C. incorrect relay setting
A. Multi-interrupt
D. Assessment of system protection performance
B. Nested Interrupt
Ans. C
C. interrupt within interrupt
312.Which of the following is not a basic category of
D. Nested Interrupt and Interrupt within interrupt
measurement?
Ans. D
A. Null
304.is The condition occurring when two or more
B. Validity
devices try to write data to a bus simultaneously
C. Direct
A. Address decoding
D. Indirect
B. Bus contention
Ans. B
C. Bus collisions
313.Use of functions is that they can be used to _____
D. Address multiplexing
and to make program more
Ans. B
understandable
305.1n memory mapped scheme, the devices are
A. Increase code duplication
viewed as
B. Decrease code duplication
A. Distinct I/O devices
C. Sub Program
B. Memory locations
Ans. B
C. Only Input devices
314.The large or surge impedance loading of a long
D. Only output devices
transmission line can be increased without
Ans. B
adversely affecting its stability by connecting a lumped
306.The process of refreshing the data In RAM to
A. Inductance in series with the line
reduce the possibility of data loss Is known as
B. Inductance in shunt with the line
A. Data cycle
C. Capacitance in shunt with the line
B. Retain cycle
D. Capacitance in series with the line
C. Regain cycle
Ans. D
D. Refresh cycle
315.As compared to oscillators, inverter provides
Ans. D
A. Low voltage output
307.The Instruction, MOV AX, 2 OH Is an example of
B. Low frequency output
A. Register addressing mode
C. Distortion less output
B. Direct-addressing mode
D. Noise less output
C. Immediate addressing mode
Ans. B
D. Based indexed addressing mode
316.
Ans. C
A ______ can be used to make automated
308.The instruction that unconditionally transfer the
potentiometer in comparison measurements.
control of execution to the specified
A. Analog to digital converter
address Is
B. Digital to analog converter
A. JMP
C. Electrometer
B. RET
D. Precision meter
C. CALL
Ans. B
D. IRET
317.
Ans. A
Depletion region of diode contains Ans. B
A. No mobile charge carriers 325.
B. A small number of mobile carriers In a transformer it is difficult to measure the efficiency
C. A large number of mobile carriers by output-Input measurement
D. The number of mobile carriers depend upon methods because
temperature A. The output Is sinusoidal and hence cannot be
Ans. A determined
318. B. Losses are abnormally high
The analog to digital converter provides ______ of input C. Efficiency of transformer Is usually high and hence
signal. extremely accurate measurements will
A. Representation be necessary
B. Quantization D. Outputs out of phase with respect to input
C. Maximum value Ans. C
D. All Information 326.
Ans. B Series capacitor compensation is used to
319. A. Increase the series reactance between load and
A higher directivity is specified by supply
A. High gain low bandwidth B. Reduce the series reactance between load and supply
B. High gain high bandwidth C. Supply the reactive power
C. Low gain low bandwidth D. Increase voltage dip on load
D. Low gain high bandwidth Ans. B
Ans. A 327.
320. Shunt reactors are needed
GSM uses A. To boost receiving end voltage under light loads
A. FDMA B. To boost receiving end voltage under heavy loads
B. TDMA C. To bring down receiving end voltage at light loads
C. Both D. To bring down receiving end voltage under heavy
D. None of above loads
Ans. C Ans. C
321. 328.
Advanced mobile phone systems (AMPS) In a transfer function gain k=0 root locus roots are
A. FDMA A. Break In point
B. TDMA B. Open loop poles
C. Both C. Break away points
D. None D. Open loop zeros
Ans. A Ans. B
322. 329.
Which Modulation has higher data rates? TDMA uses
A. AM A. Phase modulation
B. FM B. Frequency modulation
C. QAM C. Amplitude modulation
D. QPSK D. All of above
Ans. C Ans. A
323. 330.
Fly back converter is used for Output occurring due to only Input with zero Initial
A. AC-AC conditions is called
B. AC-DC A. Zero state
C. DC-DC B. Zero Input
D. DC-AC C. Absolute state
E. Both B&C D. Real state
Ans. E Ans. A
324. 331.
Large phase mercury arc rectifier is used as The maximum loads attached to a device called
A. Inverter A. Fan In
B. Rectifier B. Fan out
C. Both C. Phase In
D. None D. Phase out
Ans. B B. Modulated analog
332. C. Aligned waves
Link layer design is also called D. All of above
A. Transport layer Ans. D
B. Access layer 340.
C. Data layer Why are pole tips in DC machine chamfered?
D. Protocol design layer A. To improve commutation characteristics
E. Network layer B. To reduce armature reaction effect
Ans. C Ans. B
333. 341.
TCP/IP address is how many bits A. 0 The phase difference between the primary and
A. 16 bits secondary voltage of a transformer
B. 32 bits B. 90
C. 64 bits C. 180
D. 128 bits D. Between 30 and 60
Ans. B Ans. C
334. 342.
If two 16-bit numbers are multiplied then the result Is Why is it important to maintain an Impedance match
A. Two bytes from the source to the load when
B. Four bytes sending signals?
C. Six bytes A. To reduce external noise
D. Eight bytes B. to keep the line balanced
Ans. B C. To reduce reflected energy
335. D. To reduce attenuation
Differential amplifier uses which coupling Ans. C
A. Transformer coupling 343.
B. RC coupling Power input to a transformer at no load and rated
C. Direct coupling voltage consists of
D. None of above A. Eddy current loss
Ans. C B. Hysteresis loss
336. C. Copper loss
The main advantage of autotransformer over a two D. Core loss
winding transformer is that Ans. D
A. No cooling is required 344.
B. Hysteresis losses are minimized In a transformer, no load current
C. Eddy current losses are minimized A. leads the applied voltage, by 90
D. Only one winding is used as a result there is B. Lags the applied voltage by 90
substantial saving in material C. lags the applied voltage by somewhat less than 90
Ans. D D. Leads the applied voltage by somewhat less than 90
337. Ans. C
is In a line to ground fault on a system, the fault current 345.
is 1500 A, The-zero sequence current A. 2 Number of cycles generated in 8 pole alternator in
A. 1500A one revolution
B. 0A B. 4
C. 750 A C. 8
D. 500A D. 16
Ans. D Ans. B
338. 346.
The torque of an Induction motor is What limits design of long transmission line?
A. Directly proportional to slip A. Thermal considerations
B. Inversely proportional to slip B. Conductor area
C. Proportional to the square of slip C. Both A & B
D. Directly proportional to current D. None of above
Ans. A Ans. B
339. 347.
In which. form, waves reach at the antenna Which of following terms are related to PWM?
A. Modulated digital A. NRZ
B. RZ Laplace transform is used for solving
C. Both A. Complex equations
D. None of the above B. Differential equations
Ans. C C. Linear equation
348. D. Quadratic equations
What Is the main task of power electronics? Ans. B
A. AC-DC conversion 356.
B. AC-AC conversion If 1 Hz frequency is applied to the field of dc machine
C. DC-AC conversion armature EMF will be
D. A & C A. 1 Hz sinusoidal
Ans. A B. DC
349. C. 1 Hz square wave
The bit used for error detection and retransmission is D. None of above
named as Ans. A
A. Parity bit 357.
B. First bit Heating value is measured by
C. Low bit A. Hygrometer
D. High bit B. Barometer
Ans. A C. Altimeter
350. D. Bomb calorimeter
A. 0 In a DC machine, the angle between the stator and Ans. D
rotor fields is 358.
B. 90 Which of the following is not running cost of the
C. 180 thermal power plant?
D. 270 A. Equipment
Ans. B B. Fuel
351. C. Workers
Torque of an indicating meter depends upon D. Maintenance
A. Spring Ans. A
B. Gravity 359.
C. Both Calorific value Is usually given by unit of energy divided
D. None by
Ans. C A. Mass (usually)
352. B. Volume
If gauge of copper is increased in impedance matching C. Weight
transformer what will happen D. Density
A. Resistance will Increase Ans. A
B. Resistance will decrease 360.
C. Resistance remains the same Efficiency of thermal power plant is measured by
D. None of the above subtracting efficiency of turbine from
Ans. A A. Boiler
353. B. Condenser
A 440V, 100W bulb on 220V will behave like a C. Compressor
A. 25W D. None of these
B. 50W Ans. A
C. 75W 361.
D. None The time of power plant which is obtained by dividing
Ans. A average time by total time Is called
354. A. Plant operating factor
Doped semiconductor material has temperature B. Demand factor
coefficient of C. Plant capacity factor
A. Positive D. Diversity Factor
B. Negative Ans. A
C. Neither positive nor negative 362.
D. Either positive or 'negative Total number of stages in gas turbine power plant
Ans. A A. Four
355. B. Two
C. Six D. Companding
D. None Ans. D
Ans. A 370.
363. Frequency shift keying Is used mostly In
The method in which customer pays some fixed cost A. Radio transmission
along with Peak demand cost and total B. Telegraphy
electricity usage cost C. Telephone
A. Two-part tariff D. Satellite communication
B. Three-part tariff Ans. B
C. Commercial tariff 371.
D. None of the above LVDT (linear variable differential transformer) is a
Ans. B ______ device
364. A. Electrodynamic
Which hydel plant has lowest production capacity? B. Electromechanical
A. Rasul Barrage C. Electromagnetic
B. Dargai Hydro Plant D. Electrostatic
C. Gomal Zam Dam Ans. B
D. Duber Khawar Hydro 372.
Ans. C The autocorrelation function is
365. A. An odd function
Calorific value of which fuel is highest B. An even function
A. Anthracite C. An exponential function in to
B. Hydrogen D. None
C. Coal Ans. B
D. Natural gas 373.
Ans. B Probability density function of thermal noise is
366. A. Binomial
Which winding of transformer has less cross-sectional B. Poisson
area? C. Gaussian
A. Primary winding D. None of these
B. Secondary Winding Ans. C
C. Low voltage winding 374.
D. High voltage winding If 360 coulomb charge is stored for a time period of 30
Ans. D minutes. What will be the current?
367. A. 200mA
A helical antenna is used in satellite tracking because of B. 20A
its C. 2A
A. Circular polarization D. 20mA
B. Maneuverability Ans. A
C. Broad bandwidth 375.
D. Good front to back ratio The potential difference between two similar charges is
Ans. A A. Same
368. B. Infinite
A heterodyne frequency changer is called a C. Nil
A. Modulator D. None of above
B. Mixer Ans. C
C. Demodulator 376.
D. frequency translator Mass, in Force-voltage analogy, is analogous.to
Ans. B A. Charge
369. B. Current
The process in which the signal is first compressed C. Inductance
before modulation and expanded after D. Resistance
demodulation so as to allow the use of a uniformly Ans. C
quantizing rate is known as 377.
A. Pre emphasis Top loading is sometimes used with an antenna in order
B. De-emphasis to
C. Quantization A. Decrease its input impedance
B. Increase its height C. Putting a large resistance in series with the actual
C. Increase its effective height measuring part of the Instrument
Ans. C Ans. C
378. 386.
A rhombic antenna is a Transformers are designed to have ___ leakage
A. Resonant Induction.
B. Non resonant A. Zero
C. Either of the above B. Low
Ans., B C. High
379. D. Medium
The carrier of a 100% modulated AM wave is Ans. B
suppressed, the % power saving is _____ 387.
A. 100% The path of the magnetic flux in transformer should
B. 83% have
C. 50% A. Low reluctance
D. 66.66% B. Low resistance
Ans. D C. High reluctance
380. D. High resistance
Burning material such as wood, paper and textile Ans. A
constitute which type of fire 388.
A. Class A For transmitting power on a 20-25-km line which
B. Class B voltage should be used
C. Class C A. 5kV
D. Class D B. 11KV
Ans. A C. 33KV
381. D. 66kV
The radiation pattern of a parabolic-antenna is Ans. B
A. Omni directional 389.
B. A figure of eight Due to low budget the weight of the conductor is to be
C. Highly directional reduced by 25 %. using the same
D. None conductor material, as a power engineer what will you
Ans. C do
382. A. Reduce the voltage level
Execution of program Instruction in computer takes B. Double the voltage level
place in C. Reduce the frequency level
A. RAM D. None of the above
B. ROM Ans. B
C. Hard disk 390.
D. Mother board In a ______ current is induced with mechanical motion
Ans. A of the conductor
383. A. Transformer
The breakdown voltage in gases depends on B. Generator
A. Distance between electrodes C. Thyristor
B. Relative air density D. None of the above
C. Humidity Ans. B
D. All of these 391.
Ans. D 1000 million tons coal is required to generate 1000 MW
384. for a year, for uranium this fuel
Turbo alternators are characterized by amount to
A. Short diameter and great axial length A. 10-15%
B. Large diameters and great axial lengths B. 20-25%
Ans. A C. 30-35%
385. D. 40-45%
An ammeter is convertible to a voltmeter by Ans. C
A. Changing the scale 392.
B. Putting a large resistance in parallel with the actual E= N dφ/ dt is called
measuring part of the Instrument A. Lenz's law
B. Faraday's law B. Less volume and high pressure
C. Gauss's Law C. High volume and low pressure
D. Amperes Law D. High volume and high pressure
Ans. B Ans. C
393. 400.
In real power system constant used a + j b, j is called If a large load is disconnected suddenly from an
A. √1 alternator or a power system, then
B. √�1 A. Turbine speed increases and frequency also increases
Ans. B B. Turbine speed decreases and frequency also
394. decreases
Capacity factor =0.628, maximum demand is 325 MW, C. Turbine speed increases and frequency decrease
plant capacity is 350 MW, calculate D. Turbine speed decreases but frequency increases
load factor, Average load= 250 MW Ans. A
A. 0.8
B. 0.67
Ans. B
Actual answer is 0.76 (NTS mistakenly writes answer as
0.67)
395.
For transmission lines the standing wave ratio is the
ratio of
A. Maximum voltage to minimum voltage
B. Maximum current to minimum voltage
C. Peak voltage to RMS voltage
D. Maximum reactance to minimum reactance
Ans. A
396.
In order to improve the steady state stability of
overhead transmission lines, which of the
following methods can be adopted
A. Reducing impedance between the stations
B. Adopting quick response excitation
C. Using series capacitors to make X = √3R
D. Any of the above
Ans. D
397.
Difference between AC and DC generator?
A. The AC generators carry slip rings while DC require
commutator
B. The DC generators carry slip rings while AC
generators require a commutator
C. Both AC and DC generators carry slip rings
D. Both AC and DC generators require a commutator
Ans. A
398.
In shunt generator, the shunt winding is parallel with
the armature its advantage is
A. Single source is used to excite both
B. Eliminates need for external excitation
C. Both
D. None of above
Ans. B
399.
The turbines of run of river hydel power plant (low head
turbines) deal with which kind of
water
A. Less volume and low pressure