Model Paper with answer Q1 Which of the following has high electrical resistivity (a) Copper (b) Gold (c) Carbon (d) Silver Q2 The resistance of 200 m. long circular copper wire is 21Ω.If its thickness is 0.44mm,What is the resistivity(ohm-m) of the copper is (a) 1.597*10-8 (b) 2.507*10-8 (c) 5.597*10-6 (d) None of these Q3 Metals have temperature coefficient of resistance (a) Positive (b) negative (c) May be positive or Negative (d) None of these Q4 The resistance of two wire is 25Ω when connected in series and 6Ω when connected in parallel.The resistance of each wire is (a) 12 &13Ω (b) 15&10Ω (c) 20& 5 Ω (d) 24&1ΩQ5 A current of 3A flows through 10Ω resistor. The energy dissipated in 5sec.is (a) 450J (b) 150J (c) 250J (d) None of these Q6 Ideal current source has its internal resistance equal to (a)1Ω. (b)2Ω. (c) 0Ω (d) InfiniteΩQ7 If resistance of all three branches of star connected load is 1Ω each, then the resistance of each branch of equivalent delta load would be (a) 3Ω (b) 9Ω (c) 0.3Ω (d) 1/3ΩQ8 A p.d. of 300V is maintained across the terminals of the capacitor. The electric field strength(kV/m) between the plate gap of (0.3mm) is (a) 1000 (b) 2000 (c) 3000 (d) 4000 Q9 An 8micro-farad capacitor is connected in series with 0.5MΩ resistor. The time constant of the RC circuit is (a) 16sec. (b) 6sec (c) 5sec (d) 4sec Q10 An 8micro-farad capacitor is charged from a 100V supply. The energy stored in the c apacitor is (a) 0.004J (b) 0.0016J (c) 0.008 J (d) None of these Q11 A conductor carries a current of 100A at right angle to a magnetic field having density of 0.5 T. The force on per unit lengh of the conductor is (a) 50N (b) 500N (c) 150N (d) 5.0N Q12 A magnetic flux of 200μwb passing through a coil of 1200 turns is reversed in 0.2sec.The induced emf in the coil is (a) 12V (b) 2.4V (c) 2.2V (d) 1.2V Q13 The value of 1/√(μ0 ε0) is equal to (a) Speed of light (b) 1/ Speed of light (c) (Speed of light )2 (d) None of these (a) NΦ/I (b) NI/Φ (c) I /ΦN (d) None of these Q15 A coil of 200 turns is wound on a non- magnetic circular core of area 500mm2& the mean circumference of 400mm.The inductance of coil is (a) 628H (b) 6.28μH (c ) 62.8μH (d) None of these Q16 An alternating voltage is given by the equation v = 200Sin 314t the rms value of the voltage is (a) 141.42V (b) 282.82V (c) 14.142V (d) None of these Q17 In a transformer the induced emf i n the winding is given by (notation used have their usual me aning) (a) E = 1.11 N f Φm (b) E = 2.22 N f Φm (c) E = 4.44 N f Φm (d) None of theseQ18 A dc motor takes a n armature current of 10A at 220V.The armature resistance of the machine is 0.2Ω, flux per pole is .01wb, the no of poles are 6,and the armature has wave wound 480 conductors. The torque developed in armature is (a) 100Nm (b) 25Nm (c) 44Nm (d) 22.91Nm Q19 A,3-phase, synchronous generator has 4 pairs of pole is running with the speed of 900 rpm.The frequency of the supply would be (a) 50Hz (b) 60Hz (c) 25Hz (d) 150Hz Q20 The advantage of permanent magnet moving coil(PMMC) instrument is
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100532130 Imp Objective for Assistant Engineer Electrical by Uppcl
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8/12/2019 100532130 Imp Objective for Assistant Engineer Electrical by Uppcl
(8) A 100 V voltmeter has full-scale accuracy of 5%. Atits reading of 50 V it will give an error of(a) 10%(b) 5%
(c) 2.5%(d) 1.25%
(9) You are required to check the p. f. of an electricload. No p.f. meter is available. You would use:(a) a wattmeter(b) a ammeter, a voltmeter and a wattmeter(c) a voltmeter and a ammeter(d) a kWh meter
(10) The resistance of a field coil may be correctlymeasured by using(a) a voltmeter and an ammeter
(b) Schering bridge(c) a Kelvin double bridge(d) a Maxwell bridge
(11) An analog instrument has output(a) Pulsating in nature(b) Sinusoidal in nature(c) Which is continuous function of time and bears aconstant relation to its input(d) Independent of the input quantity
(13) A.C. voltage can be measured (using ad.c. instrument) as a value obtained(a) by subtracting the d.c. reading from it's a.c. reading.(b) Using the output function of the multimeter(c) By using a suitable inductor in series with it(d) By using a parallel capacitor with it(e) None of the above
(14) A moving coil permanent magnet ammeter can beused to measure(a) D. C. current only(b) A. C. current only(c) A. C. and D. C. currents(d) voltage by incorporating a shunt resistance(e) none of these
(15) Select the wrong statement(a) the internal resistance of the voltmeter must be high(b) the internal resistance of ammeter must be low(c) the poor overload capacity is the main disadvantage
of hot wires instrument(d) the check continuity with multimeter, the highestrange should be used.
(e) In moving iron voltmeter, frequency compensation isachieved by connecting a capacitor across its fixed coil.
(16) Which of the following instrument is suitable formeasuring both a.c. and d.c.quantities.(a) permanent magnet moving coil ammeter.(b) Induction type ammeter.(c) Quadrant electrometer.(d) Moving iron repulsion type ammeter.
(e) Moving iron attraction type voltmeter.
(17) Swamping resistance is used in movingcoil instruments to reduce error due to
(a) thermal EMF(b) temperature(c) power taken by the instrument(d) galvanometer sensitivity.
(18) A power factor meter is based on the principle of(a) electrostatic instrumentb) Electrodynamometer instrument(c) Electro thermo type instrument(d) Rectifier type instrument.
(19) A potentiometer recorder is used for(a) AC singles(b) DC signals(c) both (a) and (b)(d) time varying signals(e) none of these.
(20) Transformers used in conjunction withmeasuring instruments for measuring purposes arecalled(a) Measuring transformers(b) transformer meters
(c) power transformers(d) instrument transformers(e) pulse transformers.
(21) Leakage flux in an electrical machine is measure by(a) Ballistic galvanometer(b) Flux meter(c) Either (a) or (b)(d) Vibration galvanometer(e) CRO
(22) A C.R.O. is used to indicate(a) supply waveform(b) magnitude of the applied voltage(c) B.H. loop(d) all of these(e) Magnitude of the current flowing in it.
(23) An oscillator is a(a) an amplifier having feedback network(b) a high gain amplifier(c) a wide band amplifier(d) a untuned amplifier(e) None of these
(24) Distortion can be measured by(a) Wave meter(b) Digital filters(c) Wein bridge circuit(d) Bridge T filter circuit
(25) Series connected Q- meter is preferablefor measurement of components having(a) high impedance(b) low impedance(c) both (a) and (b)(d) high frequency(e) low capacitance
(26) A potentiometer is
(a) an active transducer(b) a passive transducer(c) a secondary transducer(d) a digital transducer(e) a current sensing transducer
(27) The basic components of a digital voltmeter are:(a) A/D converter and a counter(b) A/D converted and a rectifier(c) D/A converter and a counter(d) Ramp generator and counter(e) Comparator
(28) Which of the following electrical equipment cannotconvert ac into dc(a) diode(b) converter(c) transformer(d) mercury arc rectifier
(29) Voltage measurement are often taken by usingeither a voltmeter or(a) an ammeter(b) an ohmmeter(c) an oscillator(d) a watt-meter
(30)The electric device which blocks DC but allows AC iscalled:(a) capacitance(b) inductor(c) an oscilloscope(d) a watt-meter
(31 ) The range of an ammeter can be extended by usinga(a) shunt in series(b) shunt in parallel(c) multiplier in series(d) multiplier in parallel
(32)A device that changes one form of energy to anotheris called(a) rheostat(b) oscillator(c) transducer(d) varicap
(33) Aquadag is used in CRO to collect(a) primary electron(b) secondary electron
(c) both primary and secondary(d) none of above
(34) A vertical amplifier for CRO can be designed for(a) only a high gain(b) only a broad bandwidth
(c) a constant gain time bandwidth product(d)all of the above
(35) One of the following is active transducer(a) Strain gauge(b) Selsyn(c) Photovoltic cell(d) Photo emissive cell
(36) The dynamic characteristics of capacitivetransducer are similar to those of(a) low pass filter(b) high pass filter(c) band pass filter(d) band stop filter
(37) Thermocouples are(a) passive transducers(b) active transducers(c) both active and passive transducers(d) output transducers
(38) The size of air cored transducers as compare to ironcore counter part are(a) bigger(b) smaller(c) same
(39) From the point of view of safety, the resistance ofearthing electrode should be:(a) low(b) high(c) medium(d) the value of resistance of electrode does not effectthe safety
(40) In CRT the focusing anode is located(a) between pre accelerating and accelerating anodes(b) after accelerating anodes(c) before pre accelerating anodes(d) none of above
(41) Which transducer converts heat energy intoelectrical energy(a) I. V. D. T.(b) thermocouple(c) photoconductor(d) none of the above
(42) Which of photoelectric transducer is used forproduction of electric energy by converting solar energy(a) photo emission cell(b) photo diode(c) photo transistor(d) both (b) and (c)
(43) Which of the following instruments consumesmaximum power during measurement?(a) induction instruments(b) hot wire instruments
(c) thermocouple instruments
(d) electrodynamometer instruments(44) Which of the following meters has the bestaccurancy(a) moving iron meter
(b) moving coil meter(c) rectifier type meter(d) thermocouple meter
(45) The function of the safety resistor in ohm meter isto(a) limit the current in the coil(b) increase the voltage drop across the coil(c) increase the current in the coil
(d) protect the battery
(46) Which of the following instruments is free fromhysteresis and eddy current losses?(a) M.l. instrument(b) electrostatic instrument(c) electrodynamometer type instrument(d)all of these
(47) The dielectric loss of a capacitance can bemeasured by(a) Wien bridge(b) Owen bridge
(c) Schering bridge(d) Maxwell bridge
(48) Reed frequency meter is essentially a(a) recording system(b) deflection measuring system(c) vibration measuring system(d) oscillatory measuring system
(49) In measurements made using a Q meter, highimpedance elements should preferably be connected in(a) star(b) delta
(c) series(d) parallel
(50) A digital voltmeter measures(a) peak value(b) peak-to-peak value(c) rms value(d) average value
1. In order for a 30 volt, 90 watt lamp to work
properly in a 120 volt supply the required series
resister in ohm is
(A) 10 (B) 20
(C) 30 (D) 40
2. According to Theremin’s theorem, any linear
active network can be replaced by a single voltagesource
(A) in series with a single impedance
(B) in parallel with a single impedance
(C) in series with two impedances
(D) in parallel with two impedances
3. The internal resistance of ammeter is
(A) very small (B) very high
(C) infinite (D) zero
4. Hay bridge is used mainly for the measurement of
(A) resistance (B) inductance
(C) conductance (D) capacitance
5. Which of the following is true about series
resonance
(A) The reactance becomes zero and impedance
becomes equal to resistance
(B) The current in the circuit becomes maximum
(C) The voltage drop across inductance and capacitance
cancels each other(D) All of the above statements are correct
6. A 3-Ф, 4 wire, 400/230 v feeder supplies 3-phase
motor and an unbalanced lighting load. In this
system
(A) all four wires will carry equal current
(B) neutral wire will carry no current
(C) neutral wire will carry both motor current
and lighting load current
(D) neutral wire will carry current only when lighting load
is switched on
7. Equalizing connections are required when
paralleling two
(A) alternators
(B) compound generators
(C) series generators
(D) both (B) and (C)
8. An ideal transformer is one which
(A) has a common core for its primary and secondary
windings
(B) has no losses and magnetic leakage
(C) has core of stainless steel and windings of pure
copper metal
(D) has interleaved primary and secondary windings
9. The principle of operation of a 3-
phase induction motor is most similar to that of a
(A) synchronous motor
(B) repulsion-start induction motor(C) transformer with a shorted secondary
(D) capacitor-start, induction-run motor
8/12/2019 100532130 Imp Objective for Assistant Engineer Electrical by Uppcl
8. Pick up the nonlinear system(a) automatic voltage regulator(b) d.c. servomotor with high field excitation(c) temperature control of a furnaces using thermistor(d) speed control using SCR(e) all of these
9. Signal flow graph (SFG) is a(a) polar graph
(b) semi log graph(c) log log graph(d) a special type of graph for analyzing modem controlsystem(e) a topological representation of a set of differentialequations
10. Disadvantages of magnetic amplifier(a) time lag, less flexible, non-sinusoidal waveform(b) low power consumption and isolation of the activecircuit(c) saturation of the core(d) all of these
11. Pick up false statement regarding magneticamplifiers(a) The gate coil of an ideal magnetic amplifier haseither zero or infinite inductance(b) Resistance of control and gate winding is very small(c) Magnetic amplifier gas dropping load characteristics(d) Magnetic amplifiers are not used to control thespeed of d.c. shunt motor(e) Magnetic amplifiers can be used in automatic controlof electric drivers of higher rating.
12. High power amplification is achieved by using
(a) push pull amplifier(b) amplidyne(c) magnetic amplifier(d) DC amplifier(e) D.C. generator
13. Pick up false statement regarding servomotors(a) The d.c. servomotors are lighter than equivalent a.c.servomotors(b) The d.c. servomotors develops higher starting andreversing torque than equivalent a.c. servomotor.(c) A drag cup a.c. servomotor has one windings onstator and other on rotor(d) Output power of servomotors varies from 1/20 W to100 W
14. To reduce steady state error(a) decrease natural frequency(b) decrease damping(c) increase damped frequency(d) increase time constant(f) increase gain constant of the system
15. A good factor for Mp should be(a) less than 1
(b) lying between 1.1 and 1.5(c) more than 2.2(d) zero(e) infinity
16. Pick up false statement. Routh-Hurwitz criterion
(a) is used for determining stability of a system(b) is an algebraic procedure(c) gives the exact location of roots of the characteristicequation(d) does not indicate relative degree of stability orinstability
17. Which of the following is the time domain method ofdetermining stability of a control system
(a) Bode plot(b) Nyquist plot(c) Nicholos chart(d) Routh-Hurwitz array(e) Constant M and (fy) locus(f) Root locus technique
18. The technique which gives transient responsequickly as well as stability information is(a) Nyquist plot(b) Routh-Hurwitz criteria(c) Bode plot(d) Root locus plot
(e) Nichols plot
19. The bandwidth can be increased by use of(a) phase lag network(b) phase lead network(c) both (a) and (b) in cascade(d) both (a) and (b) in parallel(e) none of these
20. Nyquist plot is drawn on(a) semi log graph paper(b) log log graph paper(c) polar graph paper
(d) centimeter graph paper
21. If the gain margin is positive and the phase margin isnegative the system is
(a) stable
(b) unstable
(c) indeterminist
22. The Bode plot is applicable to
(a) all phase network
(b) minimum phase network
(c) maximum phase network
(d) lag lead network
(e) none of these
23. The valid relation between setting time ts and risetime tr is
(a) tr>ts
(b) ts>tr
(c) ts=tr
8/12/2019 100532130 Imp Objective for Assistant Engineer Electrical by Uppcl