I had appeared in NTPC MT-2010 in Chennai on 2 nd May ’10 under Electrical Engineering (B.Tech.) Category and surprisingly NTPC has changed their question format this time. Total number of Q were 85 (50 Technical, 35 Non-Technical) but time was 120 mins. So u can assume that the Q Paper was a bit tough. Among Non-technical the different sections were based on GK(4 Q only) DI (4-5 Q from Graph) Apti (2 Q on number series, 2 Q on Permutation Combination, 1 Q on time & work) Reasoning (1 Q on relation, 3 Q from series of pictures) English Paragraph and Q from there, Sentence assembling (total 5-6 Q) Though it was Electrical Category but 40%-45% of technical questions came from Electronics related. SO, IT’S MY ADVICE TO YOU THAT DON’T ASSUME THAT THE RECRUITER IS NTPC SO IT IS MANDATORY TO GIVE STRESS ONLY ON TRANSFORMER-ALTERNATOR-POWER SYSTEM-DC MACHINES. YOU MUST GIVE MORE STRESS ON CONTROL SYSTEM BASICS, MEASUREMENT & ELECTRONICS BASICS. I’m giving the Technical questions (from Electrical Category) as much as I can remember, 1) Steady state acceleration error of type 1 system, a. 0 b. 1 c. Infinity d. 2) Position and velocity of type 2 system,
Transcript
I had appeared in NTPC MT-2010 in Chennai on 2nd May ’10 under Electrical Engineering (B.Tech.) Category and surprisingly NTPC has changed their question format this time.
Total number of Q were 85 (50 Technical, 35 Non-Technical) but time was 120 mins. So u can assume that the Q Paper was a bit tough. Among Non-technical the different sections were based onGK(4 Q only)DI (4-5 Q from Graph)Apti (2 Q on number series, 2 Q on Permutation Combination, 1 Q on time & work)Reasoning (1 Q on relation, 3 Q from series of pictures) English Paragraph and Q from there, Sentence assembling (total 5-6 Q) Though it was Electrical Category but 40%-45% of technical questions came from Electronics related.SO, IT’S MY ADVICE TO YOU THAT DON’T ASSUME THAT THE RECRUITER IS NTPC SO IT IS MANDATORY TO GIVE STRESS ONLY ONTRANSFORMER-ALTERNATOR-POWER SYSTEM-DC MACHINES.
YOU MUST GIVE MORE STRESS ON CONTROL SYSTEM BASICS, MEASUREMENT & ELECTRONICS BASICS.I’m giving the Technical questions (from Electrical Category) as much as I can remember,
1) Steady state acceleration error of type 1 system,a. 0b. 1c. Infinityd.
2) Position and velocity of type 2 system,a. Constant, Infinity.b. Zero, Constant.c. Zero, Zero.d. Constant, Constant.
3) In a diode ‘cut-in’ & ‘forward voltage drop’a. 0.7, 0.7b. 0.7, 1c. 0.7, 0.6d. 1, 0.7
4) Potential value of α in a transistor? βa. 1.
b. 1.c. Negative.d. Between 0.95 & 0.99
5) What is the relation between α & β of a transistor?6) In SCR dv/dt protection achieved by
a. RL in Series.b. RC across.c. L in series.d. RC in Series.
7) Placing inverter between both input of S-R Flip-Flop results in,a. J-K Flip Flop.b. D Flip-Flop.c. T Flip-Flop.d. Master Slave J-K Flip-Flop.
8) Which have Max. Distortion?a. Class A Amplifier.b. Class B Amplifier.c. Class AB Amplifier.d. Class C Amplifier.
9) Which is Initial Value Theorem,4 options were there.
10) By increasing Frequency, power dissipation in CMOS,a. reduce.b. Increase.c. Unchanged.
11) Anderson Bridge used to measurea. Inductanceb. Capacitance.c.
d.12) Laplace transform of e-atsin wt.13)Lap winding is mostly suitable for
a. Low Voltage, High Current Machines.b. High Voltage, High Current Machines.c. High Voltage, Low Current Machines.d. Low Voltage, Low Current Machines.
14) Turn-on time of SCR in Series with RL circuit can be reduced by,a. Increasing ckt resis. R.b. Decreasing ckt resis R.c. Increasing ckt ind. L.d. Decreasing ckt. Ind. L.
15) In Two-Wattmeter Method of measuring power, the reading of 2 W.M. will bea. VLILcos(30+φ), VLILcos(30+φ)b. VLILcos(30–φ), VLILsin(30–φ)c. VLILcos(30–φ), VLILcos(30+φ)d. VLILcos(30–φ), VLILsin(30+φ)
16) In Railways the CB used isa. SF6.b. ABCB.c. VCB.d. OCB.
17) What is the short-circuit admittance parameter Y11 of the following п-Network? ____________Yc____________ | | | | Ya Yb | | | |
20) A question on 4 types of CRO with their application. You have to match them.21) Kirchoff’s Law is applicable for.
a. AC ckt. only.b. DC ckt. only.c. Both AC & DC ckt.d. Passive ckt. Only.
22) What is Synchronous Reactance?23) A Q was from DC M/c.; 4 type Generators(series, shunt, cumulative, ______ )
and their appl.(arc welding, booster, ______, ______ ) Given, you have to match them.
24) Q came from II-quadrant operation of DC drive.25) An inverted sawtooth wave form was given which had (-)ve Y-axis magnitudeon
30 and time value on X-axis were 5 & 7. You have to choose the correct mathematical form of that wave from 4 options.26) A simple ckt with a 20V source, a diode and a 10 Ohm resistance in series was
given, The condition was 'if the diode is ideal' then what will be the current value?27) Which is universal GATE? a. NAND & NOR. b. NAND. c. NOR.
THAT'S ALL, GOOD LUCK.
it consists of 2 sections (50 techincal + 35 aptitude ,reasoning and general awarness) ............2hrs durationcorrect ....1M and wrong..........-1/4Mfirst section is on techincal(50 bits)1.differential relay is used for which type of protectiona) internal b)2.Type of CB's used in railway service
a)air blast b)SF6 c)vacuum d)oil3.L[e^-at .sinwt]4.what are the positional and velocity constants of a type 2 system5.what type of compensation is made if a pole is added to T.F6.what are universal gatesa)NAND and NOR b)NAND c)NOR d)none of these.7.which f/f is formed if both the inputs of SR f/f are inverted.a)JK b)D c)T d)8. formula for initial value theorem9.how many circuits are to be solved in a super position theorema)equal to no of nodes b)no of sources...10.KVL is applied to which networksa)linear b)ac circuits c) dc circuits d )both ac and dc circuits11.A match the following about CRO'sp.storage cro q.sampling cror.high fre. cro s.low fre. cro12. A match the following about power plantsp.hydal 1.high initial costq.thermal 2.high maintainencer.nuclear 3.high operating costsdiesel 4.high life13.how the turn on time of an SCR can be reduced14A match the following about different scr'sp.triacq.gtor.rcts.15.how dv/dt triggering is applied to an scra) by using series RC b)placing RC across scrc)d)16.what are the values of cut in and forward voltage drops of a diodea)0.7v,0.7vb)1v ,0.6v
17.alpha value range in a transistor a)unity b)0.95 to 0.99 c)more than unity18.relation between alpha and beta in a transistor19.what is 7423a) full adder b)TTL adder c) 8 bit adder/subtractor20.A match the following about dc generatorsp. series 1.battery chargingq.shunt 2.boosterr.compound 3.transmissions.differential 4.arc welding21. A simple ckt with a dc voltage and a diode is connected to it FB conditon and a MI meter is connected to it then asked about the amount of rms value of current shown by the multimeter22.
2nd section (35 bits)consists of general awareness (5 bits),aptitude(10) ,reasoning (10) ,comprehension and grammatical mistakes(3) general awareness51.who donated land to golden temple at amritsara)akbar b)humayan c)shahjahan d)jahangir52.what is Fahrenheit 9/1153.who is christiano Ronaldo54. what a student should possess to participate in municipal council electionsaptitudeblood relations -------1time and work ..........1about volume of a cone bar chars and pie charts ..........5
reasoningserie completion of numbers ......2coding.........1non verbal reasoning ........3a no preceeding by some no and followed by bit ...1permutations and combinations .........3
Hai Friends, I'm Aditya Sarma from Aditya Engg. College (JNTUK Affiliated college, AP). My stream is C&I (ECE). The paper is an easy one (It varies from person to person) as I had
written many PSUs so I feel it as an easier one. The paper consists of 85 questions (technical-50, general ability-35) high score is required as it is having 85% weightage for the final selection.
My perfect advice for the aspirants is to prepare previous IES papers for technical section (I feel most PSUs take IES papers as reference). You can clear the written only If you score good in general ability as it is really deciding (Solving R.S Aggarwal models can do the aptitude, for reasoning apply brain, for vocabulary you should have sufficient time (do it last) paper consists of paragraph questions, Data interpretation etc.
In technical you need to score atleast 40/50, In general ability you should score atleast 28. So you will get the call for G.D and PI easily (even less scorers also be called i.e; 55/85) but chances of getting selected are less.
I completed the technical part in the first 40 minutes. As it is having mostly theory related bits and some problems (can be solved with a single formula! study Electronic measurements and instrumentation also)
I got enough time to solve general ability, I took time to think about the questions in patience they seems tough but if you got the basic well its easy. (men and work problem, proportionality problem, some gk questions (very easy ones no special preparation required)
Data interpretation seems difficult and time taking but you should solve this as every mark counts. I belong to general category I feel I have scored more than 75. The cut-off may be around 65 for general. 55 for obc not sure)
I got call for G.D and PI. My date of interview on June 29th 2010. The G.D is a good one I talked very less(Im neither an initiator nor finisher ) I talked in English (we can talk in either Hindi or English).
They have given two topics1. Caste based politics good or bad 2. Technology most used or abused. We chosen first one. I said just 2 to 3 points but I'm very attentive to the G.D. Its not an elimination round(but have 5% weightage as I said earlier) Interview weightage is 10%. Within less time I got the call for interview. I'm the first person to be interviewed. My mind was blank when I entered into interview. They (4 ppl including the head in panel) asked some questions related to favorite subject (I said Signals and systems), and some HR questions. Show patience if you are not able to answer the question no need to know everything. But try to understand what they are saying and respond well. If they ask about any experiences say about it (if you have relevant experience not software experiences) (freshers will get an easy interview. Prepare your project, prepare for the industrial training if you have. Percentage in B.Tech also plays a prominent role. Learn abt NTPC well, Be prepared to work anywhere in India. I felt I haven't done well (It happens to every one) but Thank god! At last I got selected For NTPC A Maharatna company as ET-2010, This is the 12th Psu I faced so far, I'm not able to clear many exams earlier (I'm 2009
passout). But I was placed in a great organisation like NTPC. So try and try till you reach your goal. Every thing is possible for every body but you should try hard and believe that it is going to be possible! All the best! Hi friends! I am Obli Rajesh. I got selected as Executive Trainee-2010 in NTPC. I belong to mechanical discipline. I want to share my experience about the GD & PI process of NTPC. The written test was held on 2/5/2010. The written test had 85 questions with 1/4th negative marking. The results of the written test were declared on 3rd June 2010. The total number of candidates short listed was 1647 for 438 posts. So the ratio will be 1:4.the GD & PI were held at PMI, Noida. My GD & PI was on 12-July-2010. The reporting time is 8:00 am. First, they will verify your original documents. Each one will be given a number as per their branch. For ex: Mech 1,2,3…..Electrical 1,2,3,…and so on. Then the GD will be held. Batches of 8 members will be formed. The time for GD is 10 minutes. One can speak either in hindi or English. There will be two judges. Two topics will be given. Out of which the group has to decide about which topic they are going to speak. My GD started at 10am. After the GD the PI is held. My turn came at 11:15am. It was a panel interview. There were five members in the board. One was the chairman. The panel members are very experienced. They seem to be around 50-60 yrs of age.I had my summer training in Hyundai motors. My subjects of interest are thermodynamics and refrigeration & air conditioning. Some of the questions asked to me are:
1. What are the types of clutches?2. What is the purpose of clutch?3. What is the name of the clutch used in cars?4. What is automatic transmission? How it works?5. Do you know about hydraulic clutch?6. What is the specialty of i20?7. What kind of layout used in Hyundai assembly line?8. What subject you want me to ask?9. State the Second law of thermodynamics?10. What is common between the two statements?11. What is exergy?12. What is availability?13. Draw psychrometric chart?14. How to find the dew point temperature?15. Plot Sensible cooling?16. Plot cooling and humidification?17. Do you know about sensible heat factor line?18. What is dryness fraction?19. Plot dryness fraction on T-S diagram?20. Which point represents zero dryness and which point represents dryness fraction of one?21. What apparatus will be used to measure both dry bulb and wet bulb temperature?22. Have you seen it?23. You have not even seen it?24. Does it have a handle?25. Why it should be rotated in the air?26. What is the type of cloth used to cover the bulb?27. Can I use the cloth from your shirt?28. What will be the temperature if I use it outside this room?29. Which will be higher either DBT or WBT?30. What is the state of this liquid in this bottle?
31. Will it have zero dryness fractions?32. Plot the boiling of liquid on T-S diagram?33. What is dew point depression?34. For what it is used?
Besides these I was also asked about my native place. They asked about the SAIL steel plant in my home town (Salem, TN). My interview lasted for 30-35 minutes. It wasn’t easy. It is a combination of both hr and tech. The interviewers will also try to stress you. They will make comments abt u. but be calm and collected. That will help you to sail through. The weightage given for written, GD & PI are in the ratio 85:5:10. So a good written score will definitely help you. The results were declared on 21/8/10. I am joining NTPC on 9th September 2010. ALL THE BEST.hello everybody, i m kamal gurgarappeared in NTPC -ET exam 2010 .the papaer consist of both technical and apptitude questions.my disp.was control and inst.(electronics and communication).some questions are as follow.......1. what is the use of 'aqudag'in cro?(a) .to absorb primary electrons (b).both primary and secondary (c)only secondary electrons2. modulation index in AM chnages from 0 to1 ,effect on transmitted power is-(a)no change (b)50% increase (c) (d)3.exp. for FM is given and asked to calculate modulation index and deviation.4.at a node ,sum of incoming current 5+j4 ,the outgoing will be..5.quantization error is related to..6.in satellite communication ,military use the access technique7.memeory mapped i/o and i/o mappedi/o has address lines8.12 bit address lines has memeory capacity9 .final value theorem experession.10. ques .about 8085 flags.11. limitation of kiechoffs law.12. z-transform of unit step signal 13. poission ratio given ,gauge factor asked14.FET can be used as...which device can be used as double SCR. conclusion :there is no requirement of extra preperation for this exam ,only classroom is more han enough to get success in this exam mainly covered subjects are--communication (AM,FM etc.)-refer any general book-inst. and measurment from AK swaneymicroprocessor-gawonker ,bhurchandi.for other subjects all basic books refered by teachers. thankyou and good luck.......
NTPC PRACTICE PAPER 1
The paper consists of 120 qns of technical qns and 50 qns of general aptitude.
*****1/3 of negative marking for wrong answers*****
***** NO calculator allowed*****
Section 1: Technical qns
Section 2 : General aptitude
SECTION 1
1 A system has poles at 0.01 Hz, 1 Hz and 80 Hz; zeros at 5 Hz, 100 Hz and 200 Hz. The approximate phase of the system-response at 20 Hz is A) – 90°B) 0°C) 90°D) – 180°Answer : (A)
2 In an abrupt p-n junction, the doping concentrations on the p-side and n-side are NA = 9x 1016/cm3 and ND = 1 x 1016/cm3 respectively. The p-n junction is reverse biased and the total depletion width is 3 m m. The depletion width on the p-side is A) 2.7 mmB) 0.3 mm.C) 2.25 mmD) 0.75 mmAnswer : (B)
3 A master-slave flip-flop has the characteristic that A) change in the input immediately reflected in the outputB) change in the output occurs when the state of the master is affectedC) change in the output occurs when the state of the slave is affectedD) both the master and the slave states are affected at the same timeAnswer : (C)
4 A parallel plate air-filled capacitor has plate area of l0-4 m2 and plate separation of 10-3 m. It is connected to a 0.5 V, 3.6 GHz source. The magnitude of the displacement current is (e0 = 1/36p x 10-9 F/m) A) 10 mAB) 100 mAC) 10 AD) 1.59 mAAnswer : (A)5 The phase velocity of an electromagnetic wave propagating in a hollow metallic rectangular waveguide in the TE10 mode isA)equal to its group velocityB) less than the velocity of light in free spaceC) equal to the velocity of light in free spaceD) greater than the velocity of light in free spaceAnswer : (D)
6 Noise with uniform power spectral density of N0W/Hz is passed through a filter H (w) = 2 exp(-jwtd) followed by an ideal low pass filter of bandwidth BHz. The output noise power in Watts is A) 2N0BB) 4N0BC) eN0BD) 16 N0BAnswer : (B)
7 The cascade amplifier is a multistage configuration ofA) CC-CBB) CE-CBC) CB-CCD) CE-CCAnswer : (B)
8 Consider a lossless antenna with a directive gain of +6dB. If 1 mW of power is fed to it the total power radiated by the antenna will beA) 4 mWB) 1 mWC) 7 mWD) 1/4 mWAnswer : (A)
9 The bandgap of Silicon at room temperature isA) 1.3 eVB) 0.7 eVC) 1.1 eVD) 1.4 eVAnswer : (C)
10 In a PCM system, if the code word length is increased from 6 to 8 bits, the signal to quantization noise ratio improves by the factor A) 8/6B) 12C) 16D) 8Answer : (C)
11 A device with input x(t) and output y(t) is characterized by: y(t) = x2(t). An FM signal with frequency deviation of 90 kHz and modulating signal bandwidth of 5 kHz is applied to this device. The bandwidth of the output signal is A) 370 kHzB) 190 kHzC) 380kHzD) 95kHzAnswer : (C)
12 For the polynomial P(s) = s5 + s4 + 2s3 + 2s2 + 3s + 15, the number of roots which lie in the right half of the s-plane is A) 4B) 2C) 3D) 1Answer : (B)
13 An AM signal is detected using an envelope detector The carrier frequency and modulating signal frequency are 1 MHz and 2 kHz respectively. An appropriate value for the time constant of the envelope detector is A) 500 msecB) 20 msecC) 0.2 msecD) 1 msecAnswer : (B)
14 In a PCM system, if the code word length is increased from 6 to 8 bits, the signal to quantization noise ratio improves by the factor A) 8/6B) 12C) 16D) 8Answer : (C)
15 Consider the following statements S1 and S2.S1: The b of a bipolar transistor reduces if the base width is increased.S2: The b of a bipolar transistor increases if the doping concentration in the base is increased. Which one of the following is correct?
A) S1 is FALSE and S2 is TRUEB) Both S1 and S2 are TRUEC) Both S1 and S2 are FALSED) S1 is TRUE and S2 is FALSEAnswer : (D)
16. A digital-to-analog converter with a full-scale output voltage of 3.5 V has a resolution close to 14m V. Its bit size is A) 4B) 8C) 16D) 32Answer : (B)
17. A single-phase half-controlled rectifier is driving a separately excited dc motor. The dc motor has a back emf constant of 0.5 V/rpm. The armature current is 5 A without any ripple. The armature resistance is 2W. The converter is working from a 280 V, single phase ac source with a firing angle of 80°. Under this operating condition, the speed of the motor will be A) 339 rpmB) 359 rpmC) 366 rpmD) 386 rpmAnswer : (C)
17. In relation to the synchronous machines, which one of the following statements is false? A) In salient pole machines, the direct-axis synchronous reactance is greater than the quadrature-axis synchronous reactanceB) The damper bars help the synchronous motor self startC) Short circuit ratio is the ratio of the field current required to produce the rated voltage on open circuit to the rated
armature currentD) The V-curve of a synchronous motor represents the variation in the armature current with field excitation, at a given output powerAnswer : (C)
18. A parallel plate air-filled capacitor has plate area of l0-4 m2 and plate separation of 10-3 m. It is connected to a 0.5 V, 3.6 GHz source. The magnitude of the displacement current is (e0 = 1/36p x 10-9 F/m) A) 10 mAB) 100 mAC) 10 AD) 1.59 mAAnswer : (A)
19 The 8085 assembly language instruction that stores the content of H and L registers into the memory locations 2050H and 2051H, respectively, is A) SPHL 2050HB) SPHL2051HC) SHLD 2050HD) STAX 2050HAnswer : (C)
20 If E is the electric field intensity, Ñ(Ñ x E ) is equal to A) EB) | E |C) null vectorD) zeroAnswer : (D)
21 The insulation strength of an EHV transmission line is mainly governed byA) load power factorB) switching over-voltagesC) harmonicsD) coronaAnswer : (B)
22.The Q – meter works on the principle ofA) mutual inductanceB) self inductanceC) series resonanceD) parallel resonanceAnswer : (C)
23.A 800 kV transmission line is having per phase line inductance of 1.1 mH/km and per phase line capacitance of 11.68 nF/km. Ignoring the length of the line, its ideal power transfer capability in MW isA) 1204 MWB) 1504 MWC) 2085 MWD) 2606 MWAnswer : (C)
24.In a PCM system, if the code word length is increased from 6 to 8 bits, the signal to quantization noise ratio improves by the factor A) 8/6B) 12C) 16D) 8Answer : (C)
25. At an industrial sub-station with a 4 MW load, a capacitor of 2 MVAR is installed to maintain the load power factor at 0.97 lagging. If the capacitor goes out of serivce, the load power factor becomes A) 0.85B) 1.00C) 0.80 lagD) 0.90 lagAnswer : (C)
26. The conduction loss versus device current characteristic of a power MOSFET is best approximated by A) a parabolaB) a straight line
C) a rectangular hyperbolaD) an exponentially decaying functionAnswer : (A)
27. High Voltage DC (HVDC) transmission is mainly used for A) bulk power transmission over very long distancesB) inter-connecting two systems with the same nominal frequencyC) eliminating reactive power requirement in the operationD) minimizing harmonics at the converter stationsAnswer : (A)
28. For the equation,s3 – 4s2+ s + 6 = 0the number of roots in the left half of s-plane will be
A) 0B) 1C) 2D) 3Answer : (C)
29. For the function f(x) = x2 e-x, the maximum occurs when x is equal to A) 2B) 1C) 0D) -1Answer : (B)
29.The drain of an n-channel MOSFET is shorted to the gate so that VGS = VDS. The threshold voltage (VT) of MOSFET is 1 V. If the drain current (ID) is 1 mA for VGS = 2V, then for VGS = 3V, ID is A) 2 mAB) 3 mAC) 9 mAD) 4 mAAnswer : (D)
30. The first and the last critical frequency of an RC-driving point impedance function must respectively be A) a zero and a poleB) a zero and a zeroC) a pole and a poleD) a pole and a zeroAnswer : (D)
31. In what range should Re(s) remain so that the Laplace transform of the function e(a+2)t+5 exits? A) Re (s) > a + 2B) Re (s) > a + 7C) Re (s) < 2D) Re (s) > a + 5Answer : (A)
32.A parallel plate air-filled capacitor has plate area of l0-4 m2 and plate separation of 10-3 m. It is connected to a 0.5 V, 3.6 GHz source. The magnitude of the displacement current is (e0 = 1/36p x 10-9 F/m) A) 10 mAB) 100 mAC) 10 AD) 1.59 mAAnswer : (A)33.For the polynomial P(s) = s5 + s4 + 2s3 + 2s2 + 3s + 15, the number of roots which lie in the right half of the s-plane is A) 4B) 2C) 3D) 1Answer : (B)
34. The phase velocity of an electromagnetic wave propagating in a hollow metallic rectangular waveguide in the TE10 mode is A) equal to its group velocityB) less than the velocity of light in free spaceC) equal to the velocity of light in free spaceD) greater than the velocity of light in free spaceAnswer : (D)
35.A device with input x(t) and output y(t) is characterized by: y(t) = x2(t). An FM signal with frequency deviation of 90 kHz and modulating signal bandwidth of 5 kHz is applied to this device. The bandwidth of the output signal is A) 370 kHzB) 190 kHzC) 380kHzD) 95kHzAnswer : (C)
36. The Q – meter works on the principle ofA) mutual inductanceB) self inductanceC) series resonanceD) parallel resonanceAnswer : (C)
37. The Fourier transform of a conjugate symmetric function is alwaysA) imaginaryB) conjugate anti-symmetricC) realD) conjugate symmetricAnswer : (C)
38. An ideal op-amp is an ideal A) voltage controlled current sourceB) voltage controlled voltage sourceC) current controlled current sourceD) current controlled voltage sourceAnswer : (B)
q-1 A circuit has a resistance of 11 W, a coil of inductive reactance 120 W, and a capacitor with a 120-W reactance, all connected in series with a 110-V, 60-Hz power source. What is the potential difference across each circuit element?
Q-2 Applying DeMorgan’s theorem to the expression , we get
A) (A+B)+CB) A(B + C)C) Both A & BD) None of above
Q-4 Refer Below figure to Determine the resonant frequency…
A) 123.4 kHzB) 61.7 kHzC) 45.97 kHzD) 23.1 kHz
Q-4 Express the decimal number 57 in binary.
A) 100101B) 111010C) 110010D) 111001
Q-5 A vertical electric dipole antenna
a) radiates uniformly in all directions.b) radiates uniformly in all horizontal directions, but more strongly in the vertical direction.c) radiates most strongly and uniformly in the horizontal directionsd) does not radiate in the horizontal directions
Q-6 A particle oscillates according to the equation y=5.0 cos 23 t, where y is in centimeters. Find its frequency of oscillation and its position at t=0.15 s.
a) f = 23 Hz, y = -4.8 cmB) f = 3.7 Hz, y = -5.0 cmC) f = 3.7 Hz, y = -4.8 cmD) f = 3.7 Hz, y = +4.8 cm
Q-7 A 10.0-µF capacitor is in series with a 40.0-W resistance, and the combination is connected to a 110-V, 60.0-Hz line. Calculate (a) the capacitive reactance, (b) the impedance of the circuit, (c) the current in the circuit, (d) the phase angle between current and supply voltage
A) (a) 0.0038W (b) 305W (c) 0.415 A (d) voltage lags by 8.58°B) (a) 266W (b) 269W (c) 0.409 A (d) voltage lags by 81.4°C) (a) 16 kW (b) 72 kW (c) 2.75 A (d) voltage lags by 6.63°D) (a) 2.6 kW (b) 262W (c) 0.256 MA (d) voltage leads by 81.4°
Q-8 A circuit has a resistance of 11 W, a coil of inductive reactance 120 W, and a capacitor with a 120-W reactance, all connected in series with a 110-V, 60-Hz power source. What is the potential difference across each circuit element?
A ) To match the frequency range of a signal to a particular channel.B ) To reduce the bandwidth of a signal.C ) To select one radio channel from a wide range of transmitted channels.D ) To allow a number of signals to make use of a single communications channel.
Q-10 A second step to further increase system capacity is a digital access method called TDMA (Time Division Multiple Access). Using the same frequency channelization and reuse as FDMA analog but adding a time sharing element, the effective capacity is:
A) DoubledB) TripledC) Reduced by one thirdD) Unchanged
Q-11 What are Pseudo-Random noise sequences, or P/N Sequences?
A) P/N Sequences are known sequences which exhibit the properties or chracteristics of random sequencesB) P/N Sequences can be used to logically isolate users on the same physical (frequency) channelC) P/N Sequences appear as random noise to everyone else, except to the transmitter and intended receiverD) All of the above
Q-12 An op-amp integrator has a square-wave input. The output should be
A ) a sine wave.B) a triangle waveC) a square wave.D) pure DC.
Q-13 What is the relationship between the series and parallel resonant frequencies of a quartz crystal?
A) They are equal.B) Parallel resonant frequency is approximately 1 kHz higher than series resonant frequencyC) Series resonant frequency is approximately 1 kHz higher than parallel resonant frequency.D) none of the above
Q-14 Refer Below figure to Determine the resonant frequency…
A) 123.4 kHzB) 61.7 kHzC) 45.97 kHzD) 23.1 kHz
Q-15 Which FET amplifier(s) has (have) a phase inversion between input and output signals?
A) common-gateB) common-drainC) common-sourceD) all of the above
section -1 b.
1. The order of the differential equation2 34 t2d y dyy edt dt_ _ −+ _ _ + =_ _is
(A) 1 (B) 2 (C) 3 (D) 4
2. The Fourier series of a real periodic function has onlyP. Cosine terms if it is evenQ. Sine terms if it is evenR. Cosine terms if it is oddS. Sine terms if it is oddWhich of the above statements are correct?
(A) P and S (B) P and R (C) Q and S (D) Q and R
3. A function is given ( ) 2 f t = sin t + cos2t. Which of the following is true?(A) f has frequency components at 0 and 1/2p Hz(B) f has frequency components at 0 and 1/p Hz(C) f has frequency components at 1/2p and 1/p Hz(D) f has frequency components at 0, 1/2p and 1/p Hz 4. A fully charged mobile phone with a 12V battery is good for a 10minute talktime.Assume that, during the talk-time, the battery delivers a constant currentof 2A and its voltage drops linearly from 12 V to 10V as shown in the figure. Howmuch energy does the battery deliver during this talk-time?
(A) 220J (B) 12kJ (C) 13.2kJ (D) 14.4kJ 5. In an n-type silicon crystal at room temperature, which of the following can havea concentration of 19 3 4 ×10 cm− ?(A) Silicon atoms (B) Holes(C) Dopant atoms (D) Valence electrons 6. The full form of the abbreviations TTL and CMOS in reference to logic families are
(A) Triple Transistor Logic and Chip Metal Oxide Semiconductor(B) Tristate Transistor Logic and Chip Metal Oxide Semiconductor10mint010V12Vv (t) (C) Transistor Transistor Logic and Complementary Metal Oxide Semiconductor(D) Tristate Transistor Logic and Complementary Metal Oxide Silicon 7. The ROC of Z-transform of the discrete time sequence( ) ( ) ( )n n1 1x n u n u n 1 is3 2_ _ _ _= _ _ − _ _ − −_ _ _ _(A)1 1z3 2< < (B)1z2> (C)1z3< (D) 2 < z < 3 8. The magnitude plot of a rational transfer function G(s) with real coefficients isshown below. When of the following compensators has such a magnitude plot?(A) Lead compensator (B) Lag compensator(C) PID compensator (D) Lead-lag compensator 9. A white noise process X(t) with two-sided power spectral density 1×10-10 W/Hz isinput to a filter whose magnitude squared response is shown belowThe power of the output process Y(t) is given by
(A) 7 5 ×10− W (B) 6 1×10− W (C) 6 2 ×10− W (D) 5 1×10− W 10. Which of the following statements is true regarding the fundamental mode of themetallic waveguides shown?(A) Only P has no cutoff-frequency (B) Only Q has no cutoff-frequency(C) Only R has no cutoff-frequency (D) all three have cutoff-frequencyP. Coaxial Q. CylindricalR:Rectangular−40dB20dBG(jw)logw−10kHz 10kHz1( )2H fX(t) Y (t)F 11. A fair coin is tossed 10times. What is the probability that ONLY the first twotosses will yield heads?(A)212_ __ __ _(B)21021C2_ __ __ _(C)1012_ __ __ _
(D)101021C2_ __ __ _ 12. If the power spectral density of stationary random process is a sine-squaredfunction of frequency, the shape of its autocorrelation is(A) (B) (C) (D)13. ( ) ( ) 10 1unitcircle1 f zIf f z c c z , then dz is given byz− += + __
(A) 2pc1 (B) ( ) 0 2p 1 + c (C) 1 2pjc (D) ( ) 0 2pj 1 + c 14. In the interconnection of ideal sources shown in the figure, it is known that the60V source is absorbing powerWhich of the following can be the value of the current source _ ?
(A) 10A (B) 13A (C) 15A (D) 18A 15. The ratio of the mobility to the diffusion coefficient in a semiconductor has theunits
(A) 1 V− (B) 1 em× V− (C) 1 V × cm− (D) V . s 16. In a microprocessor, the service routine for a certain interrupt starts from a fixedlocation of memory which cannot be externally set, but the interrupt can bedelayed or rejected. Such an interrupt is(A) non-maskable and non-vectored (B) maskable and non-vectored(C) non-maskable and vectored (D) maskable and vectored_+−60V12A+ − 20VR (t)
tR (t)tR (t)tR (t)t 17. If the transfer function of the following network is( )( )0iV s 1V s 2 s CR=+The value of the load resistance RL is
(A) R/4 (B) R/2 (C) R (D) 2R 18. Consider the systemdx Ax Bu with A 1 0 and B pdt 0 1 q= + = _ = _ _ _ _ _where p and q arearbitrary real numbers. Which of the following statements about thecontrollability of the system is true?(A) The system is completely state controllable for any nonzero values of p and q(B) Only p=0 and q=0 result in controllability(C) The system is uncontrollable for all values of p and q(D) We cannot conclude about controllability from the given data 19. For a message signal ( ) ( ) m m t = cos 2pf t and carrier of frequency fc, which of thefollowing represents a single side band (SSB) signal?(A) ( ) ( ) m c cos 2pf t cos 2pf t (B) ( ) c cos 2pf t(C) ( ) c m cos __2p f + f t (D) ( ) ( ) m c __1 + cos 2pf t cos 2pf t 20. Two infinitely long wires carrying current are as shown in the figure below. Onewire is in the y-z plane and parallel to the y-axis. The other wise is in the x-yplane and parallel to the x-axis. Which components of the resulting magnetic fieldare non-zero at the origin?(A) x, y, z components (B) x, y components(C) y, z components (D) x, z componentsR
Ci V+−0 V+−L R1A1Azxy 21. Consider two independent random variables X and Y with identical distributions.The variables X and Y take values 0, 1 and 2 with probabilities1 1 1, and2 4 4respectively. What is the conditional probability P (X + Y = 2| X − Y = 0) ?(A) 0 (B)116(C)16(D) 1 22. The Taylor series expansion ofsinxat x is given byx= p− p(A)( )2 x1 ...3!− p+ + (B)( )2 x1 ...3!− p
− − + (C)( )2 x1 ...3!− p− + (D)( )2 x1 ...3!− p− + + 23. If a vector field V__is related to another vector field A__through V = Ñ × A,__ __whichof the following is true? Note: C and SC refer to any closed contour and anysurface whose boundary is C.(A)C C S_ V × d = __ A × dS__ ___ __ _____ _ (B)C C S_ A × d = __ V × dS__ ___ __ _____ _(C)C C S_ Ñ × V × d = __ Ñ × A × dS__ ___ __ _____ _ (D)C C S_ Ñ × A × d = __ V × dS__ ___ __ _____ _ 24. Given that F(s) is the one-sided Laplace transform of f(t), the Laplace transformof ( )t0
_ f t dt is(A) sF (s) − f (0) (B) ( ) 1F ss(C) ( )s0_ F t dt (D) ( ) ( ) 1F s f 0s__ − 25. Match each differential equation in Group I to its family of solution curves fromGroup II.Group – I Group – IIP.dy ydx x= 1. CirclesQ.dy ydx x= − 2. Straight linesR.dy xdx y= 3. HyperbolasS.dy xdx y= −(A) P-2,Q-3,R-3,S-1 (B) P-1,Q-3,R-2,S-1(C) P-2,Q-1,R-3,S-3 (D) P-3,Q-2,R-1,S-2 26. The eigen values of the following matrix are-1 3 5-3 -1 60 0 3_ _ __ _(A) 3,3 + 5j,6 − j (B) −6 + 5j,3 + j,3 − j
(C) 3 + j,3 − j,5 + j (D) 3, −1 + 3j, −1 − 3j 27. An AC source of RMS voltage 20V with internal impedance ( ) S Z = 1 + 2j W feeds aload of impedance ( ) L Z = 7 + 4j W in the figure below. The reactive powerconsumed by the load is
(A) 8VAR (B) 16VAR (C) 28VAR (D) 32VAR 28. The switch in the circuit shown was on position a for a long time, and is moved toposition b at time t=0. The current i(t) for t>0 is given by(A) 125t ( ) 0.2e u t mA − (B) 1250t ( ) 20e u t mA −(C) 1250t ( ) 0.2e u t mA − (D) 1000t ( ) 20e u t mA −( ) L Z = 7 + 4j W( ) S Z = 1 + 2j W20Ð0ºV+−+−5kWi (t)10kW a b100V0.5μF 0.3μF0.2μF 29. In the circuit shown, what value of RL maximizes the power delivered to RL?(A) 2.4W (B)83W (C) 4W (D) 6W30. The time domain behavior of an RL circuit is represented by( Rt /L ) ( )0diL Ri V 1 Be sint u t .dt+ = + −For an initial current of ( ) 0 Vi 0 ,R= the steady state value of the current is givenby(A) ( ) 0 Vi tR® (B) ( ) 0 2V
i tR®(C) ( ) 0 ( ) Vi t 1 BR® + (D) ( ) 0 ( ) 2Vi t 1 BR® + 31. In the circuit below, the diode is ideal. The voltage V is given by(A) ( ) i min V,1 (B) ( ) i max V,1 (C) ( ) i min −V,1 (D) ( ) i max −V,1 32. Consider the following two statements about the internal conditions in ann-channel MOSFET operating in the active regionS1: The inversion charge decreases from source to drainS2: The channel potential increases from source to drainWhich of the following is correct?(A) Only S2 is true+−i V 100V4W 4WX −V +− +X 4W VL R+−i V1W 1W+ V −1A (B) Both S1 and S2 are false(C) Both S1 and S2 are true, but S2 is not a reason for S1(D) Both S1 and S2 are true, and S2 is a reason for S1 33. In the following astable multivibrator circuit, which properties of v0(t) depend onR2?(A) Only the frequency(B) Only the amplitude(C) Both the amplitude and the frequency(D) Neither the amplitude nor the frequency
34. In the circuit shown below, the op-amp is ideal, the transistor hasVBE = 0.6V and b = 150. Decide whether the feedback in the circuit is positive ornegative and determine the voltage V at the output of the op-amp(A) Positive feedback, V=10 V(B) Positive feedback, V=0 V(C) Negative feedback, V=5 V(D) Negative feedback, V=2 V 35. A small signal source ( ) 6i v t = A cos20t + B sin10 t is applied to a transistoramplifier as shown below. The transistor has ie b = 150 and h = 3kW. Whichexpression best approximates ( ) 0 V t(A) ( ) ( 6 )0 v t = −1500 A cos20t + Bsin10 t(B) ( ) ( 6 )0 v t = −150 A cos20t + B sin10 t(C) ( ) 60 v t = −1500B sin10 t(D) ( ) 60 v t = −150Bsin10 t4 R3 R( ) 0 v tC2 R1 R−+V1.4kW+−5V5kW10V20kW12V900W100nF( ) i v t100kW 3kW100nF10μF
( ) 0 v t 36. If X = 1 in the logic equation _X + Z{Y + (Z + XY)} _ {X + Z(X + Y)} = 1, then _(A) Y=Z (B) Y = Z (C) Z=1 (D) Z=0 37. What are the minimum number of 2 to 1 multiplexers required to generate a 2input AND gate and a 2 input Ex-OR gate?
(A) 1 and 2 (B) 1 and 3 (C) 1 and 1 (D) 2 and 2 38. Refer to the NAND and NOR latches shown in the figure. The inputs ( ) 1 2 P ,P forboth the latches are first made (0, 1) and then, after a few seconds, made (1, 1).The corresponding stable outputs (Q1, Q2) are(A) NAND: first (0, 1) then (0, 1) NOR: first (1, 0) then (0, 0)(B) NAND: first (1, 0) then (1, 0) NOR: first (1, 0) then (1, 0)(C) NAND: first (1, 0) then (1, 0) NOR: first (1, 0) then (0, 0)(D) NAND: first (1, 0) then (1, 1) NOR: first (0, 1) then (0, 1) 39. What are the counting stages (Q1, Q2) for the counter shown in the figure below?(A) 11,10,00,11,10,.... (B) 01,10,11,00,01,....(C) 00,11,01,10,00,.... (D) 01,10,00,01,10,....2 P1 P2 Q1 Q2 P1 P2 Q1 QClock JK Flip Flop JK Flip Flop1 J1 K1 Q1 Q2 J2 K2 Q2 Q2 Q 1 Q 40. A system with transfer function H(z) has impulse response h(.) defined ash(2)=1, h(3)=-1 and h(k)=0 otherwise. Consider the following statements( )( )
S1:H z is a low pass filterS2 :H z is a FIR filterWhich of the following is correct?(A) Only S2 is true(B) Both S1 and S2 are false(C) Both S1 and S2 are true, and S2 is a reason for S1(D) Both S1 and S2 are true, but S2 is not a reason for S1 41. Consider a system whose input x and output y are related by the equationy (t) x (t )h(2 ) d¥−¥= _ − t t tWhere h(t) is shown in the graphWhich of the following four properties are possessed by the system?BIBO: Bounded input gives a bounded outputCausal: The system is causalLP: The system is low passLTI: The system is linear and time invariant(A) Causal, LP(B) BIBO, LTI(C) BIBO, Causal, LTI(D) LP, LTI 42. The 4 point Discrete Fourier Transform (DFT) of a discrete time sequence{1, 0, 2, 3} is(A) __0, −2 + 2j,2, −2 − 2j (B) __2,2 + 2j,6,2 − 2j (C) __6,1 − 3j,2,1 + 3j (D) __6, −1 + 3j,0, −1 − 3j 43. The feedback configuration and the pole-zero locations of ( ) 22s 2s 2G ss 2s 2− +=+ +areshown below. The root locus for negative values of k, i.e. for −¥ < k < 0, hasbreakaway/break in points and angle of departure at pole P (with respect to thepositive real axis) equal to(A) ± 2 and 0ºError! Not a valid link.(B) ± 2 and 45º
(C) ± 3 and 0º(D) ± 3 and 45º0 th(t)++−K G(s)Im (s)o ×o ×PRe(s)44. An LTI system having transfer function22s 1s 2s 1++ +and input x(t)=sin(t+1) is insteady state. The output is sampled at a rate wS rad/s to obtain the final output{y(k)}. Which of the following is true?(A) y(.) is zero for all sampling frequencies wS(B) y(.) is nonzero for all sampling frequencies wS(C) y(.) is nonzero for ws>2, but zero for ws>2(D) y(.) is zero for ws>2 but nonzero for ws>2 45. The unit step response of an under-damped second order system has steadystate value of -2. Which one of the following transfer functions has theseproperties?(A) 22.24s 2.59s 1.12−+ +(B) 23.82s 1.91s 1.91−+ +(C) 22.24s 2.59s 1.12−− +
(D) 23.82s 1.91s 1.91−− + 46. A discrete random variable X takes values from 1 to 5 with probabilities as shownin the table. A student calculates the mean of X and 3.5 and her teachercalculates the variance of X as 1.5. Which of the following statements is true?( )k 1 2 3 4 5P X = k 0.1 0.2 0.4 0.2 0.1(A) Both the student and the teacher are right(B) Both the student and the teacher are wrong(C) Both the student is wrong but the teacher is right(D) The student is right but the teacher is wrong 47. A message signal given by( ) 1 21 1m t cos t sin t2 2_ _ _ _= _ _ w − _ _ w_ _ _ _Is amplitude modulated with a carrier of frequency wc to generate( ) ( ) c s t = __1 + m t cos w t
(A) 8.33% (B) 11.11% (C) 20% (D) 25% 48. A communication channel with AWGN operating at a signal to noise ratio SNR>>1and bandwidth B has capacity C1. If the SNR is doubled keeping B constant, theresulting capacity C2 is given by(A) 2 1 C » 2C (B) 2 1 C » C + B (C) 2 1 C » C + 2B (D) 2 1 C » C + 0.3B49. A magnetic field in air is measured to be0 2 2 2 2x yB B ˆy ˆxx y x y_ _= _ − _ _ + + ___What current distribution leads to this field? [Hint: The algebra is trivial incylindrical coordinates.](A) 0
2 20B ˆz 1J ,r 0x y_ _= _ _ ¹ μ _ + __(B) 02 20B ˆz 2J ,r 0x y_ _= _ _ ¹ μ _ + __(C) J = 0,r ¹ 0_(D) 02 20B ˆz 1J ,r 0x y_ _= _ _ ¹ μ _ + __ 50. A transmission line terminates in two branches, each of length l/4, as shown.The branches are terminated by 50W loads. The lines are lossless and have thecharacteristic impedances shown. Determine the impedance Z1 as seen by thesource(A) 200W (B) 100W (C) 50W (D) 25WCommon Data Questions: 51 & 52Consider a silicon p-n junction at room temperature having the followingparameters:Doping on the n-side = 1×1017cm-3Depletion width on the n-side = 0.1μmDepletion width on the p-side =1.0μmIntrinsic carrier concentration = 1.4×1014F. cm-1Thermal voltage = 26mVPermittivity of free space = 8.85×10-14F. cm-1Dielectric constant of silicon = 12
51. The built in potential of the junction(A) is 0.70V(B) is 0.76V(C) is 0.82V(D) cannot be estimated from the data givenl / 40 Z = 100W0 Z = 100Wl / 4 L Z = 50WL Z = 50Wl / 40 Z = 50Wi z 52. The peak electric field in the device is(A) 0.15 MV.cm-1, directed from p-region to n-region(B) 0.15 MV.cm-1, directed from n-region to p-region(C) 1.80 MV.cm-1, directed from p-region to n-region(D) 1.80 MV.cm-1, directed from n-region to p-regionCommon Data Questions: 53 & 54The Nyquist plot of a stable transfer function G(s) is shown in the figure. We areinterested in the stability of the closed loop system in the feedback configurationshown. 53. Which of the following statements is true?(A) G(s) is an all-pass filter(B) G(s) has a zero in the right-half plane(C) G(s) is the impedance of a passive network(D) G(s) is marginally stable 54. The gain and phase margins of G(s) for closed loop stability are(A) 6dB and 180º (B) 3dB and 180º (C) 6dB and 90º (D) 3dB and 90ºCommon Data Questions: 55 & 56The amplitude of a random signal is uniformly distributed between -5V and 5V 55. If the signal to quantization noise ratio required in uniformly quantizing the signalis 43.5dB, the step size of the quantization is approximately
(A) 0.0333V (B) 0.05V (C) 0.0667V (D) 0.10V 56. If the positive values of the signal are uniformly quantized with a step size of0.05V, and the negative values are uniformly quantized with a step size of 0.1V,the resulting signal to quantization noise ratio is approximately
(A) 46dB (B) 43.8dB (C) 42dB (D) 40dB++−G(s)Re−j-1 -0.5Im Linked Answer Questions: Q.57 to Q.60 Carry Two Marks EachStatement for Linked Answer Questions: 57 & 58Consider the CMOS circuit shown, where the gate voltage VG of the n-MOSFET isincreased from zero, while the gate voltage of the p-MOSFET is kept constant at3 V. Assume that, for both transistors, the magnitude of the threshold voltage is1 V and the product of the transconductance parameter and the (W/L) ratio, i.e.the quantity ( ) 2μCox W/ L , is 1mA × V− . 57. For small increase in VG beyond 1V, which of the following gives the correctdescription of the region of operation of each MOSFET?(A) Both the MOSFETs are in saturation region(B) Both the MOSFETs are in triode region(C) n-MOSFET is in triode and p-MOSFET is in saturation region(D) n-MOSFET is in saturation and p-MOSFET is in triode region 58. Estimate the output voltage V0 for VG=1.5V. [Hint: Use the appropriate currentvoltage equation for each MOSFET, based on the answer to Q.57](A)14 V2− (B)14 V2+ (C)34 V2− (D)34 V
2+Statement for Linked Answer Questions: 59 & 60Two products are sold from a vending machine, which has two push buttons P1and P2. When a button is pressed, the price of the corresponding product isdisplayed in a 7-segment display.If no buttons are pressed, ‘0’ is displayed, signifying ‘Rs. 0’.If only P1 is pressed, ‘2’ is displayed, signifying ‘Rs. 2’.If only P2 is pressed, ‘5’ is displayed, signifying ‘Rs. 5’.If both P1 and P2 are pressed, ‘E’ is displayed, signifying ‘Error’.The names of the segments in the 7-segment display, and the glow of the displayfor ‘0’, ‘2’, ‘5’ and ‘E’, are shown belowG V3V5V0 V Consider(i) push button pressed/not pressed is equivalent to logic 1/0 respectively(ii) a segment glowing / not glowing in the display is equivalent to logic 1/0Respectively 59. If segments a to g are considered as functions of P1 and P2, then which of thefollowing is correct?(A) g = P1 + P2,d = c + e (B) 1 2 g = P + P ,d = c + e(C) 1 2 g = P + P ,e = b + c (D) 1 2 g = P + P ,e = b + c 60. What are the minimum numbers of NOT gates and 2-input OR gates required todesign the logic of the driver for this 7-segment display?(A) 3 NOT and 4 OR (B) 2 NOT and 4 OR(C) 1 NOT and 3 OR (D) 2 NOT and 3 OR
Answer Keys1 B 2 A 3 B 4 C 5 C 6 C 7 A8 D 9 B 10 A 11 C 12 B 13 D 14 A15 A 16 D 17 C 18 C 19 C 20 D 21 C22 D 23 B 24 B 25 A 26 D 27 A 28 B29 C 30 A 31 D 32 D 33 A 34 D 35 D36 D 37 A 38 C 39 A 40 A 41 B 42 D43 B 44 A 45 B 46 B 47 C 48 B 49 C50 D 51 B 52 B 53 C 54 C 55 C 56 D57 A 58 59 B 60 D
SECTION 2
APTITUDE QUESTIONS
1.If 2x-y=4 then 6x-3y=?(a)15(b)12(c)18(d)10
Ans. (b)2.If x=y=2z and xyz=256 then what is the value of x?
(a)12(b)8(c)16(d)6
Ans. (b)3. (1/10)18 - (1/10)20 = ?(a) 99/1020(b) 99/10(c) 0.9(d) none of theseAns. (a)4.Pipe A can fill in 20 minutes and Pipe B in 30 minsand Pipe C canempty the same in 40 mins.If all of them worktogether, find the timetaken to fill the tank(a) 17 1/7 mins(b) 20 mins(c) 8 mins(d) none of theseAns. (a)5. Thirty men take 20 days to complete a job working 9hours a day.Howmany hour a day should 40 men work to complete thejob?(a) 8 hrs(b) 7 1/2 hrs(c) 7 hrs
(d) 9 hrsAns. (b)6. Find the smallest number in a GP whose sum is 38and product 1728(a) 12(b) 20(c) 8(d) none of theseAns. (c)7. A boat travels 20 kms upstream in 6 hrs and 18 kmsdownstream in 4hrs.Find the speed of the boat in still water and thespeed of thewater current?(a) 1/2 kmph(b) 7/12 kmph(c) 5 kmph(d) none of theseAns. (b)8. A goat is tied to one corner of a square plot ofside 12m by a rope7m long.Find the area it can graze?(a) 38.5 sq.m(b) 155 sq.m(c) 144 sq.m(d) 19.25 sq.mAns. (a)9. Mr. Shah decided to walk down the escalator of atube station. Hefound that if he walks down 26 steps, he requires 30seconds toreach the bottom. However, if he steps down 34 stairshe would onlyrequire 18 seconds to get to the bottom. If the timeis measured fromthe moment the top step begins to descend to thetime he steps offthe last step at the bottom, find out the height ofthe stair way insteps?Ans.46 steps.10. The average age of 10 members of a committee isthe same as it was4 years ago, because an old member has been replacedby a youngmember. Find how much younger is the new member ?
Ans.40 years.11. Three containers A, B and C have volumes a, b, andc respectively;and container A is full of water while the other twoare empty. Iffrom container A water is poured into container Bwhich becomes 1/3full, and into container C which becomes 1/2 full, howmuch water isleft in container A?12. ABCE is an isosceles trapezoid and ACDE is arectangle. AB = 10and EC = 20. What is the length of AE?Ans. AE = 10.13. In the given figure, PA and PB are tangents to thecircle at A andB respectively and the chord BC is parallel totangent PA. If AC = 6cm, and length of the tangent AP is 9 cm, then whatis the length ofthe chord BC?Ans. BC = 4 cm.15 Three cards are drawn at random from an ordinarypack of cards.Find the probability that they will consist of a king,a queen and an ace.Ans. 64/2210.16. A number of cats got together and decided to killbetween them999919 mice. Every cat killed an equal number ofmice. Each catkilled more mice than there were cats. How many catsdo you thinkthere were ?Ans. 991.17. If Log2 x - 5 Log x + 6 = 0, then what would thevalue / values ofx be?Ans. x = e2 or e3.18. The square of a two digit number is divided byhalf the number.After 36 is added to the quotient, this sum is thendivided by 2.The digits of the resulting number are the same asthose in theoriginal number, but they are in reverse order. The
ten's place ofthe original number is equal to twice the differencebetween itsdigits. What is the number?Ans. 4619.Can you tender a one rupee note in such a mannerthat there shallbe total 50 coins but none of them would be 2 paisecoins.?Ans. 45 one paisa coins, 2 five paise coins, 2 tenpaise coins, and 1twenty-five paise coins.20.A monkey starts climbing up a tree 20ft. tall. Eachhour, it hops3ft. and slips back 2ft. How much time would it takethe monkey toreach the top?Ans.18 hours.21. What is the missing number in this series? 8 214 6 11 ? 14 6 18 12Ans. 922. A certain type of mixture is prepared by mixingbrand A at Rs.9 akg. with brand B at Rs.4 a kg. If the mixture is worthRs.7 a kg., howmany kgs. of brand A are needed to make 40kgs. ofthe mixture?Ans. Brand A needed is 24kgs.23. A wizard named Nepo says "I am only three times myson's age. Myfather is 40 years more than twice my age. Togetherthe three of usare a mere 1240 years old." How old is Nepo?Ans. 360 years old.24. One dog tells the other that there are two dogs infront of me.The other one also shouts that he too had two behindhim. How many arethey?Ans. Three.25. A man ate 100 bananas in five days, each dayeating 6 more thanthe previous day. How many bananas did he eat on thefirst day?Ans. Eight.26. If it takes five minutes to boil one egg, how long
will it take toboil four eggs?Ans. Five minutes.27. The minute hand of a clock overtakes the hour handat intervals of64 minutes of correct time. How much a day does theclock gain or lose?Ans. 32 8/11 minutes.28. Solve for x and y: 1/x - 1/y = 1/3, 1/x2 + 1/y2= 5/9.Ans. x = 3/2 or -3 and y = 3 or -3/2.29. Daal is now being sold at Rs. 20 a kg. During lastmonth its ratewas Rs. 16 per kg. By how much percent should a familyreduce itsconsumption so as to keep the expenditure fixed?Ans. 20 %.30. Find the least value of 3x + 4y if x2y3 = 6.Ans. 10.31. Can you find out what day of the week was January12, 1979?Ans. Friday.32. A garrison of 3300 men has provisions for 32 days,when given at arate of 850 grams per head. At the end of 7 days areinforcementarrives and it was found that now the provisions willlast 8 daysless, when given at the rate of 825 grams per head.How, many more mencan it feed?Ans. 1700 men.33. From 5 different green balls, four different blueballs and threedifferent red balls, how many combinations of ballscan be chosentaking at least one green and one blue ball?Ans. 3720.34. Three pipes, A, B, & C are attached to a tank. A &B can fill itin 20 & 30 minutes respectively while C can empty itin 15 minutes.If A, B & C are kept open successively for 1 minuteeach, how soonwill the tank be filled?Ans. 167 minutes.
35. A person walking 5/6 of his usual rate is 40minutes late. What ishis usual time? Ans. 3 hours 20 minutes.
36.For a motorist there are three ways going from CityA to City C. Byway of bridge the distance is 20 miles and toll is$0.75. A tunnelbetween the two cities is a distance of 10 miles andtoll is $1.00 forthe vehicle and driver and $0.10 for each passenger. Atwo-lanehighway without toll goes east for 30 miles to city Band then 20miles in a northwest direction to City C.
1. Which is the shortest route from B to C
(a) Directly on toll free highway to City C(b) The bridge(c) The Tunnel(d) The bridge or the tunnel(e) The bridge only if traffic is heavy on the tollfree highway
Ans. (a)
2. The most economical way of going from City A toCity B, in terms oftoll and distance is to use the
(a) tunnel(b) bridge(c) bridge or tunnel(d) toll free highway(e) bridge and highway
Ans. (a)
3. Jim usually drives alone from City C to City Aevery working day.His firm deducts a percentage of employee pay forlateness. Which
factor would most influence his choice of the bridgeor the tunnel ?
(a) Whether his wife goes with him(b) scenic beauty on the route(c) Traffic conditions on the road, bridge and tunnel(d) saving $0.25 in tolls(e) price of gasoline consumed in covering additional10 miles on thebridge
Ans. (a)
4. In choosing between the use of the bridge and thetunnel the chieffactor(s) would be:I. Traffic and road conditionsII. Number of passengers in the carIII. Location of one's homes in the center oroutskirts of one of thecitiesIV. Desire to save $0.25
(a) I only(b) II only(c) II and III only(d) III and IV only(e) I and II only
Ans. (a)
37.The letters A, B, C, D, E, F and G, not necessarilyin that order,stand for seven consecutive integers from 1 to 10D is 3 less than AB is the middle termF is as much less than B as C is greater than DG is greater than F
1. The fifth integer is(a) A(b) C(c) D(d) E
(e) F
Ans. (a)
2. A is as much greater than F as which integer isless than G(a) A(b) B(c) C(d) D(e) E
Ans. (a)
3. If A = 7, the sum of E and G is(a) 8(b) 10(c) 12(d) 14(e) 16
Ans. (a)
4. A - F = ?(a) 1(b) 2(c) 3(d) 4(e) Cannot be determined
Ans. (a)
5. An integer T is as much greater than C as C isgreater than E. Tcan be written as A + E. What is D?(a) 2(b) 3(c) 4(d) 5(e) Cannot be determined
Ans. (a)
6. The greatest possible value of C is how muchgreater than thesmallest possible value of D?(a) 2(b) 3(c) 4(d) 5(e) 6
Ans. (a)
38.1. All G's are H's2. All G's are J's or K's3. All J's and K's are G's4. All L's are K's5. All N's are M's6. No M's are G's
1. If no P's are K's, which of the following must betrue?
(a) All P's are J's(b) No P is a G(c) No P is an H(d) If any P is an H it is a G(e) If any P is a G it is a J
Ans. (a)
2. Which of the following can be logically deducedfrom the conditionsstated?
(a) No M's are H's(b) No M's that are not N's are H's(c) No H's are M's(d) Some M's are H's(e) All M's are H's
Ans. (a)
3. Which of the following is inconsistent with one ormore of theconditions?
(a) All H's are G's(b) All H's that are not G's are M's(c) Some H's are both M's and G's(d) No M's are H's(e) All M's are H's
Ans. (a)
4. The statement "No L's are J's" isI. Logically deducible from the conditions statedII. Consistent with but not deducible from theconditions statedIII. Deducible from the stated conditions togetherwith the additionalstatement "No J's are K's"
(a) I only(b) II only(c) III only(d) II and III only(e) Neither I, II nor III
Ans. (a)
39.In country X, democratic, conservative and justiceparties havefought three civil wars in twenty years. TO restorestability anagreement is reached to rotate the top officesPresident, PrimeMinister and Army Chief among the parties so that eachparty controlsone and only one office at all times. The three topoffice holdersmust each have two deputies, one from each of theother parties. Eachdeputy must choose a staff composed of equally members
of his or herchiefs party and member of the third party.
1. When Justice party holds one of the top offices,which of thefollowing cannot be true
(a) Some of the staff members within that office arejustice party members(b) Some of the staff members within that office aredemocratic partymembers(c) Two of the deputies within the other offices arejustice party members(d) Two of the deputies within the other offices areconservativeparty members(e) Some of the staff members within the other officesare justiceparty members.
Ans. (a)
2. When the democratic party holds presidency, thestaff of the primeminister's deputies are composedI. One-fourth of democratic party membersII. One-half of justice party members and one-fourthof conservativeparty membersIII. One-half of conservative party members andone-fourth of justiceparty members.
(a) I only(b) I and II only(c) II or III but not both(d) I and II or I and III(e) None of these
Ans. (a)
3. Which of the following is allowable under the rulesas stated:
(a) More than half of the staff within a given officebelonging to asingle party(b) Half of the staff within a given office belongingto a single party(c) Any person having a member of the same party ashis or herimmediate superior(d) Half the total number of staff members in allthree officesbelonging to a single party(e) Half the staff members in a given office belongingto partiesdifferent from the party of the top office holder inthat office.
Ans. (a)
4. The office of the Army Chief passes fromConservative to Justiceparty. Which of the following must be fired.
(a) The democratic deputy and all staff membersbelonging to Justice party(b) Justice party deputy and all his or hers staffmembers(c) Justice party deputy and half of his Conservativestaff members inthe chief of staff office(d) The Conservative deputy and all of his or herstaff membersbelonging to Conservative party(e) No deputies and all staff members belonging toconservative parties.
Ans. (a)
40.In recommendations to the board of trustees atuition increase of$500 per year, the president of the university said"There were nostudent demonstrations over the previous increases of
$300 last yearand $200 the year before". If the president'sstatement is accuratethen which of the following can be validly inferredfrom theinformation given:I. Most students in previous years felt that theincreases werejustified because of increased operating costs.II. Student apathy was responsible for the failure ofstudents toprotest the previous tuition increases.III. Students are not likely to demonstrate over newtuition increases.
(a) I only(b) II only(c) I or II but not both(d) I, II and III(e) None
Ans. (a)
41. The office staff of XYZ corporation presentlyconsists of threebookeepers--A, B, C and 5 secretaries D, E, F, G, H.The management isplanning to open a new office in another city using 2bookeepers and 3secretaries of the present staff . To do so they planto seperatecertain individuals who don't function well together.The followingguidelines were established to set up the new officeI. Bookeepers A and C are constantly finding faultwith one anotherand should not be sent together to the new office as ateamII. C and E function well alone but not as a team ,they should beseperatedIII. D and G have not been on speaking terms andshouldn't go togetherIV Since D and F have been competing for promotionthey shouldn't be ateam
1.If A is to be moved as one of the bookeepers,whichof the followingcannot be a possible working unit.
A.ABDEHB.ABDGHC.ABEFHD.ABEGH
Ans.B
2.If C and F are moved to the new office,how manycombinations arepossible
A.1B.2C.3D.4
Ans.A
3.If C is sent to the new office,which member of thestaff cannot gowith C
A.BB.DC.FD.G
Ans.B
4.Under the guidelines developed,which of thefollowing must go to thenew office
A.BB.DC.ED.G
Ans.A
5.If D goes to the new office,which of the followingis/are true
I.C cannot goII.A cannot goIII.H must also go
A.I onlyB.II onlyC.I and II onlyD.I and III only
Ans.D
42.After months of talent searching for anadministrative assistant tothe president of the college the field of applicantshas been narroweddown to 5--A, B, C, D, E .It was announced that thefinalist would bechosen after a series of all-day group personalinterviews wereheld.The examining committee agreed upon the followingprocedure
I.The interviews will be held once a weekII.3 candidates will appear at any all-day interviewsessionIII.Each candidate will appear at least onceIV.If it becomes necessary to call applicants foradditonalinterviews, no more 1 such applicant should be askedto appear thenext weekV.Because of a detail in the written applications,itwas agreed thatwhenever candidate B appears, A should also bepresent.VI.Because of travel difficulties it was agreed that Cwill appear foronly 1 interview.1.At the first interview the following candidatesappear A,B,D.Which
of the follwing combinations can be called for theinterview to beheld next week.
A.BCDB.CDEC.ABED.ABC
Ans.B
2.Which of the following is a possible sequence ofcombinations forinterviews in 2 successive weeks
A.ABC;BDEB.ABD;ABEC.ADE;ABCD.BDE;ACD
Ans.C
3.If A ,B and D appear for the interview and D iscalled foradditional interview the following week,which 2candidates may beasked to appear with D?
I. AII BIII.CIV.EA.I and IIB.I and III onlyC.II and III onlyD.III and IV only
Ans.D
4.Which of the following correctly state(s) theprocedure followed bythe search committee
I.After the second interview all applicants haveappeared at least onceII.The committee sees each applicant a second timeIII.If a third session,it is possible for allapplicants to appear atleast twice
A.I onlyB.II onlyC.III onlyD.Both I and II
Ans.A
43. A certain city is served by subway lines A,B and Cand numbers 1 2and 3When it snows , morning service on B is delayedWhen it rains or snows , service on A, 2 and 3 aredelayed both in themorning and afternoonWhen temp. falls below 30 degrees farenheit afternoonservice iscancelled in either the A line or the 3 line,but not both.When the temperature rises over 90 degrees farenheit,the afternoonservice is cancelled in either the line C or the3 line but not both.When the service on the A line is delayed orcancelled, service on theC line which connects the A line, is delayed.When service on the 3 line is cancelled, service onthe B line whichconnects the 3 line is delayed.Q1. On Jan 10th, with the temperature at 15 degreefarenheit, itsnows all day. On how many lines will service beaffected, including both morning and afternoon.(A) 2
(B) 3(C) 4(D) 5Ans. D
Q2. On Aug 15th with the temperature at 97 degreesfarenheit it beginsto rain at 1 PM. What is the minimum numberof lines on which service will be affected?(A) 2(B) 3(C) 4(D) 5Ans. C
Q3. On which of the following occasions would servicebe on thegreatest number of lines disrupted.(A) A snowy afternoon with the temperature at 45degree farenheit(B) A snowy morning with the temperature at 45 degreefarenheit(C) A rainy afternoon with the temperature at 45degree farenheit(D) A rainy afternoon with the temperature at 95degree farenheitAns. B
44. In a certain society, there are two marriagegroups, red andbrown. No marriage is permitted within a group. Onmarriage, malesbecome part of their wives groups; women remain intheir own group.Children belong to the same group as their parents.Widowers anddivorced males revert to the group of their birth.Marriage to morethan one person at the same time and marriage to adirect descendantare forbiddenQ1. A brown female could have hadI. A grandfather born RedII. A grandmother born RedIII Two grandfathers born Brown(A) I only
(B) III only(C) I, II and III(D) I and II onlyAns. D
Q2. A male born into the brown group may have(A) An uncle in either group(B) A brown daughter(C) A brown son(D) A son-in-law born into red groupAns. A
Q3. Which of the following is not permitted under therules as stated.(A) A brown male marrying his father's sister(B) A red female marrying her mother's brother(C) A widower marrying his wife's sister(D) A widow marrying her divorced daughter'sex-husbandAns. B
Q4. If widowers and divorced males retained theirgroup they had uponmarrying which of the following would be permissible (Assume that noprevious marriage occurred)(A) A woman marrying her dead sister's husband(B) A woman marrying her divorced daughter'sex-husband(C) A widower marrying his brother's daughter(D) A woman marrying her mother's brother who is awidower.Ans. D
Q5. I. All G's are H'sII. All G's are J's or K'sIII All J's and K's are G'sIV All L's are K'sV All N's are M'sVI No M's are G's45. There are six steps that lead from the first tothe second floor.No two people can be on the same stepMr. A is two steps below Mr. CMr. B is a step next to Mr. DOnly one step is vacant ( No one standing on that step
)Denote the first step by step 1 and second step bystep 2 etc.1. If Mr. A is on the first step, Which of thefollowing is true?(a) Mr. B is on the second step(b) Mr. C is on the fourth step.(c) A person Mr. E, could be on the third step(d) Mr. D is on higher step than Mr. C.Ans: (d)2. If Mr. E was on the third step & Mr. B was on ahigher step thanMr. E which step must be vacant(a) step 1(b) step 2(c) step 4(d) step 5(e) step 6Ans: (a)3. If Mr. B was on step 1, which step could A be on?(a) 2&e only(b) 3&5 only(c) 3&4 only(d) 4&5 only(e) 2&4 onlyAns: (c)4. If there were two steps between the step that A wasstanding andthe step that B was standing on, and A was on a higherstep than D , Amust be on step(a) 2(b) 3(c) 4(d) 5(e) 6Ans: (c)
5. Which of the following is false
i. B&D can be both on odd-numbered steps in oneconfigurationii. In a particular configuration A and C must eitherboth an oddnumbered steps or both an even-numbered stepsiii. A person E can be on a step next to the vacant
step.(a) i only(b) ii only(c) iii only(d) both i and iiiAns: (c)
46. Six swimmers A, B, C, D, E, F compete in a race.The outcome is asfollows.i. B does not win.ii. Only two swimmers separate E & Diii. A is behind D & Eiv. B is ahead of E , with one swimmer interveningv. F is a head of D1. Who stood fifth in the race ?(a) A(b) B(c) C(d) D(e) EAns: (e)2. How many swimmers seperate A and F ?(a) 1(b) 2(c) 3(d) 4(e) cannot be determinedAns: (d)3. The swimmer between C & E is(a) none(b) F(c) D(d) B(e) AAns: (a)
4. If the end of the race, swimmer D is disqualifiedby the Judgesthen swimmer B finishes in which place(a) 1(b) 2(c) 3(d) 4(e) 5
Ans: (b)47. Five houses lettered A,B,C,D, & E are built in arow next to eachother. The houses are lined up in the order A,B,C,D, &E. Each of thefive houses has a colored chimney. The roof andchimney of eachhousemust be painted as follows.i. The roof must be painted either green,red ,oryellow.ii. The chimney must be painted either white, black,or red.iii. No house may have the same color chimney as thecolor of roof.iv. No house may use any of the same colors that theevery next houseuses.v. House E has a green roof.vi. House B has a red roof and a black chimney1. Which of the following is true ?(a) At least two houses have black chimney.(b) At least two houses have red roofs.(c) At least two houses have white chimneys(d) At least two houses have green roofs(e) At least two houses have yellow roofsAns: (c)2. Which must be false ?(a) House A has a yellow roof(b) House A & C have different color chimney(c) House D has a black chimney(d) House E has a white chimney(e) House B&D have the same color roof.Ans: (b)3. If house C has a yellow roof. Which must be true.(a) House E has a white chimney(b) House E has a black chimney(c) House E has a red chimney(d) House D has a red chimney(e) House C has a black chimneyAns: (a)4. Which possible combinations of roof & chimney canhouseI. A red roof 7 a black chimneyII. A yellow roof & a red chimneyIII. A yellow roof & a black chimney
(a) I only(b) II only(c) III only(d) I & II only(e) I&II&IIIAns: (e)48. Find x+2y(i). x+y=10(ii). 2x+4y=20Ans: (b)
49. Is angle BAC is a right angle(i) AB=2BC(2) BC=1.5ACAns: (e)50. Is x greater than y(i) x=2k(ii) k=2yAns: (e)
4.A box contains 16 balls of 4 different colors green blue yellow &red each. if you were to close your eyes and pick them at random , how many marbles must you take out to be sure that there at least two of one colour among the marbles picked out.A. 4 b. 5 c. 6 d. 14 ans.b
Electrical Engineering
1. What is causal system? 2. Shunt reactor is used in EHV transmission line for 3. 20w, 40W, & 200w lamps are connected to three phases if neutral wire breaks then which lamp will fuse first? 1) 20 2)40 3)200 three lamps will fuse together. 4. Synchronous machine can be operated at both lagging and leading power factor 5 What does synchronous speed mean? 6. Frequency of emf generated per rotation of rotor is equal to…. 7. DC machine having wave winding is wounded as lap winding what will be the effect on emf generated
8 Which is remain unchanged in transformer action? 9. In transformer windings are connected………….?
10. In general how transformer is rated?11. What is given on the name plate of motor? 1) KW 2) KVA 3) output shaft power12. Short circuit test of transformer gives what?13. Transformer core are laminated for what purpose?14. What is supply voltage for heavy industry .1) 33KV 2) 11KV 3) 132 KV 4) 66KV15. Basic structure SCR as a two transistor i.e. how they are connected?16. What is Triac?17. System admittance is (G+jB) what is reactive power absorbed if the voltage is V
KV? (1) V (square)*B (2) V (square)*g ….18. In series R-L circuit what is phase difference between the voltage drop across R
and L?19. Power factor is cosine (delta ) delta is the angle between 1) phase voltage phase
current 2)Line voltage lone current 3) phase voltage line current 4) line voltage phase current.
20. Laplace of exp (-at)?21. For series R-L-C circuit the load will be capacitive if the frequency is 1) greater
than the resonant frequency 2) less than the resonant frequency 3)….22. In Wien’s bridge which circuit elements determine the frequency range?23. What is the output if two booster having duty cycle K and (K-1) are connected in
series?24. If a DC shunt motor is loaded from unloaded condition what will be effect of on
terminal voltage?25. A second wire system having one pole one right half of the s-plane. When the
system will be stable?26. A system having repetitive pole what will be effect on the gain at the cross over
frequency?27. Hollow conductor is used to reduce corona loss how does it reduce the loss?28. In DC machine how voltage is related to flux?29. Nature of current and voltage in the armature and at the terminal in DC
machine.30. Motor acts on the principle of …………..rule31. Which instrument measure both ac and dc?32. How the rotation of induction motor is reversed?33. If 3-phaseof a 3- phase balance load are reversed what will be the effect on the
line current?34. If the rating of VAR absorber is 50MVAR at 400KV. What will the VAR absorbed
by the absorber at 300KV?35. In regenerative breaking of DC series motor what is done?36. Definitions of Fourier transform?37. Laplace of f(t) is F(S) what is Laplace of f(t+T) .38. Z-transform of sampled function x(n) for n>0.39. Laplace transform of impulse function.40. Z-transform of unity.
41. How many slip rings are there in 3phase synchronous motor?42. How the speed of synchronous motor is controlled?43. Speed control of induction motor?44. When power supply is supplied to heater coil it glows while simple wire does
not glow. Why?45. A synchronous generator having inertia constant 4 and having rating of
100MVA. What will be energy stored by the machine?46. A transformer having ratio 20:1. The secondary load is 0.6 ohm and the voltage
across it is 6 V what will be the primary current?47. A RC circuit having r=0.8ohm, c=2.5micofarad what will be the time constant?48. Find load impedance if c=0.1 micro farad?49. Two capacitors connected in series the equivalent capacitance is 0.03uf and
when connected in parallel the equivalent capacitance is 0.16uf find out the ratio of the two capacitance?
50. An L-c circuit having frequency 1/sqrt (LC) what will the equivalent impedance?51. An inverting op-am having input with resistance in series and a capacitance in
feedback operates as a……………….?52. A current having fundamental and third harmonics what will be the rms value
of the current?53. Peak to peak value of voltage if rms voltage is 100V.54. Rms voltage.55. What is the approx efficiency of nuclear power plant?56. What is the average current of a single phase full wave rectifier firing at angle
alpha?57. What is the function of freewheeling diode?58. When SCR stops conduction? (holding current)59. For measuring current why shunt resistance is used?60. For economic operation of plant what is the condition?(taking into account the
penalty factor)61. Incremental fuel cost of two plants is given and a load is given. Find out the load
sharing for economic operation of the plant?62. A two port network is represented by ABCD parameters. What will be condition
for the two port network to be symmetrical?63. Size of the conductor is determined by ……………….64. Which Surface is suitable for grounding?
Hai, this is sandhya from the ELECTRICAL discipline... I have attended for the test conducted for executive trainee on 12th april 2009. The paper wsas for 170 marks out of which 120 ---- from the electrical discipline and 50----- from aptitude for a duration of 2 hours with 1 /4 th negative marking The paper was not tough..and merely needs 3-4 weeks preparation. It mostly consisted of Basics but from the depth of it.. The aptitude part can be answered even without any preparation and it consisted of questions from vocabulary and general aptitude from profit loss , ages etc... and preparing any competitive exam aptitude book is enough.. Coming to the subject.. most of the questions were covered from electronics.. and that to Basics and related to IGBTS, FETS, BJTS which none of us expects.. and moreover all the topics from 4 years were covered including Mathematics...some of the questions which i could remember were1) Definition of synchronuous speed2) Steady state error formula3) Maths: Questions related to laplace, Z- transforms, and Forier series.. were asked
4) What is the transmisssion voltage for the bulk industries..5) Questions related to power plant applications and construction6) Electronics: from IGBTS, JFETS, BJT as mentioned above7) And also questions related to instrumentation were also asked So totally the paper needs a preparation from all subjects...All the best to all Future
Hi All,
I have taken the written of NTPC ltd on April12th 2009
Pattern 120 question technical 50 Aptitude
Weightage of subjects as follows
TechnicalInstrumentation----15-20 questionCommunication ------ 15-20Control systems -------15-20Microprocessors8085 ---4-5Digital electronics ------9-11Signal systems ------- 3-4Electronics ------------13-15
AptitudeEnglish ----20Quant------20Reasoning---10
Question which I remember as followsTechnical
1)Gain bandwidth product of 2 stage CE amplifier compared to single stagea). greater b). lesser c). same etc
2)Early effect in transistor leads ina). Fast switch b). slow switch etc
3)MOSFET acts as aa). Resistor b). inductor c). capcitor etc
4)Normal PH is a)7 b)2 c)5 etc
5)Gave number of bits as 8 and max voltage as 100V asked to calculate resolution
6)strain guage working principlea). resistor c). capacitor etc
7)Class AB propertya). More efficiency b). avoids crossoverdistrotion
25)Wheat stone bidge used for measuringa) resistor b) inducator etc
26)RLC ckt responsea) exponentially increasing b) decreasing etc
27)FET is aa) VCVS b) CCCS c) VCCS d) CCVS
28)Gave a TF asked to identify the poles and zeroes
29)Gave a characteristic equation asked to find number poles in right side
30)Optical wavelength range asked
31)LASER abbreviation---------
32)Schotky TTL diode is used to reducea) delay b) gates c) power d) none
Aptitude
English1) Prepostions 3 to 4
2)Synonyms & antonyms
3)grammer
Quant1)Ratios
2)Profit & loss
3)Bar graph given asked to find several things
4)Puzzles related persons going to different offices
5)Words coding etc
That’s all I remember All the Best
NTPC PAPER ON 4th MAY KOLKATA Technical ( control and instrumentation):1. expression for δ(n): u(n)-u(n-1)/ u(n-1)-u(n+1)/ u(n)+u(n+1)/...
2. numerical on a photodiode: to calculate the responsivity/sensitivity when a specified no of incident photons cause a specified no of electron generation.
3. for a radioactive sample which decays to 12.5% of its initial value in x days, the half life is given by..
4. connect two 1Ω resistors in series, then connect two 1H inductors across one of the resistors such that the ckt looks like a 1Ω resistor in series with a Π-section of a resistor and two inductors. With the series resistance on the i/p side, calc the transfer function of this ckt5. AC signal conditioning is used for inductive and capacitive/resistive/piezoelectric transducers/all of the above. 6. lower useful input limit of a transducer is determined by…
7. air-cored inductors are used for low frequency/high frequency/equal frequency operations.
8. given 4 pole-zero plots identify which one corresponds to the driving point impedance of a series resonant ckt.
9. given four unit-circle plots identify the one corresponding to a bandpass filter.
10. the sequence (2,3,4,3) is circularly even/circularly odd/circularly zero/both circularly even and odd.
11. z-transform of 3n u(n).
12. match the following with their characteristics: LED/LCD/nixie tube/optical fibre.
13. a 4 kHz signal is sampled at thrice the Nyquist rate and sent through a channel with error ≤1%. Calc the bandwidth of the channel.
14. given an op-amp ckt obtain an expression for o/p voltage.
15. no. of encirclements made about the origin of the nyquist plot of the open loop TF:1/[(s-1)(s+2)(s+3)].
16. given a two port network in the form of a T find o/p admittance in terms of y-parameters.
17. for a repeater in a PCM cable identify the correct sequence of actions amongst threshold/equalization/etc.
18. o/p of a delta modulator when a ramp input is fed to it.
19. steady state error with ramp i/p for a type-0 system.
20. creeping occurs in energy meters bcoz….
21. ultrasonic method of flow measurement cannot be used in liquids with air bubbles/has less attenuation in air compared to liquid-identify the false statement (if any) among these.
22. major cause of losses in a fibre optic cable: dispersion/total internal refraction/presence of core and cladding/…
23. which layer in the OSI model is concerned with printer buffering,etc: network/session/transport/…
24. given some function F(jω) calc its inverse CTFT.
25. relation between laplace and z-transform: s=z/ s=ln z/ s=( ln z/T) /…
26. maxm and minm probability error among ASK,PSK,FSK,DPSK etc
27. which of the following is a non linear modulation scheme: PAM/QAM/PCM/…
28. match the following functions: e-t , e-t + et, sin(πt) with causal and stable system, causal and unstable system, etc.
29. given a ckt with a 50 Ω resistor in series between two voltage sources of 10 V and 5 V magnitude calc power delivered by 5 V source.
30. laplace transform of e-3tu(t)+e2tu(-t).
31. which photodetector has output affected by own intrinsic noise: PN/APD/PIN/all.
32. inverse laplace transform of 1/s2[d/ds(e-3s/s)]
33. when I mode is added to proportional control system stability increases/ decreases/ steady state performance deteriorates/damping increases.
34. reset control is another name for integral/derivative/proportional/…. Control.
35. time response of system having transfer function 625/(s2+25) will be of the form…
36. given some transfer function calc the peak response time.
37. the nyquist sampling rate of the function [sin(at)/t]2 will be…
38. the feedback topology that results in increased i/p and o/p impedance is current series/voltage series/current shunt voltage shunt.
39. numerical on cardiac output calculation given heart rate and volume per beat.
40. in an ECG instrumentation amplifier the differential gain is provided by 1st stage/2nd stage/mismatched resistors/output stage.
41. repeat ques 40 above for the classic 3-op amp instrum amplifier.
42. EMG signals are of the order of mV/V/μV/…
43. computer assisted tomography is used for…
44. numerical on electrostatic instrument, to calculate deflection given spring constant, torque etc.
45. to prevent loading of a ckt i/p impedance of a CRO should bee high/low/inductive/capacitive.
46. addition of a zero to a 2nd order underdamped system results in increase/decrease of rise time and increase/decrease of peak overshoot.
47. for PI ctrl we obtain improved bandwidth/improved steady state performance/ worsened steady state performance/…
48. SNR of normal AM system is comparable/3 dB lower/3 dB higher/6 dB lower over DSB-SC and SSB system.
49. which is an effective measure of the noise related performance of an amplifier: SNR/noise ratio/thermal noise/shot noise.
50. given baseband signal freq and carrier freq calc which of the freq given will not be present for conventional AM.
51. distinction between FM and PM at high frequencies.
52. which of these has the least propagation delay RTL/ECL/I2L/CMOS.
53 switching speed of CMOS is affected/unaffected by changes in supply voltage.
54. which of these provides a measure of heart rate P/QRS complex/T/none of these.
55. given a ckt of a logarithmic amplifier you had to identify what ckt was it.
56. JFET can operate in depletion/enhancement/both/none of the above modes.
57. when a BJT operates in saturation the junctions are fwd biased/reverse biased/…
58. BIBO stability criterion implies that poles are within/outside/on the unit circle.
59. for faithful amplification of low amplitude signals the cut-off/active/saturation regions of a transistor is used.
60. lissajous pattern of a signal rotates 36 times per minute. if the oscillator frequency is 560 kHz then the unknown freq is…
61. % resolution of a 10 bit ADC.
62. to obtain 10 mV resolution on 5 V range how many bit DAC is to be used..
63. why is LCD preferred to LED.
64. how will 0.6973 be displayed on 10 V range of a 4 ½ digit multimeter.
65. which of the following cannot be used for an automatic feedback temp ctrl system thermocouple/thermometer/thermistor/IC sensor.
66. y(n)=x(-n+3) is an example of a linear/non linear and shift variant/invariant system.
67. the falling body method is used to determine viscosity/humidity/….
68. which of these methods of viscosity measurement gives greatest accuracy falling body method/rotating cylinder method/both/…
69. some question on gas chromatography
70.a device having a rotor with 3 Y-connected coils and a stator is likely to be a synchro/RVDT/control transformer/…
71. in a twisted ring counter the initial count is 1000. after the 4th clock pulse its state will be….
72. a 240 kHz signal is given into a 3 bit binary ripple counter. The lowest o/p freq obtainable is….
73. for parity bit checking which of the following gates can be used XOR/NAND/OR/XNOR.
74. why is a BJT called so..
75. identify the expression for gauge factor of a strain gauge among the given options.
76. in a semiconductor strain gauge as tensile strain is applied what changes take place in the n and p areas..
77. how does a radioactive level gauging system work…
78. a capacitive transducer measuring level works on the principle of change in distance between plates/change in dielectric strength/…
79. for maximum power transfer in an AC circuit the condition to be satisfied is ZL+ZS=0/XL+XS=0/none of these/….where l and s refers to load and source resp.
80. find the transfer function from a block diagram.
81. synchronous ctrs are preferred to asynchronous ctrs bcoz they are faster/glitches at the output can be avoided/both/none of these.
82. the lissajous figure formed on an oscilloscope looks like the English figure of 8. if the vertical channel input is 1 kHz the horizontal input freq is….
83. IE=IC for a transistor in saturation/cutoff/active/both saturation and active regions.
84. reproducibility of measurements is called accuracy/precision/linearity/none of these.
85. which of these is not strictly a static characteristic accuracy/precision/tolerance/linearity.
86. the shunt coil in a Q meter has resistance of the order of mΩ/Ω/kΩ/..
87. for measuring inductance of high Q coils the bridge used is Maxwell-wien/Schering/…
88. which of these measures inductance in terms of capacitance Maxwell and hay/Maxwell and Schering/hay and Schering/…
89. in a flip-flop with preset and clear inputs both are applied simultaneously/clear is cleared when preset is applied/preset is cleared when clear is applied/….
90. what happens when the RET instruction is encountered by 8085
91. a 1024*8 memory chip needs how many address lines…
92. what happens when the PUSH instruction is encountered by 8051.
93. in FM relation between no of sidebands w.r.t. modulating freq
94. numerical on DPSK.
95. a multiplexer accepts input data and provides one output all the time/one output at a time/many outputs at a time/many outputs all the time.
96. pulse modulation is essentially a process of multiplexing/….
97. wave shape is altered by clipper/clamper/voltage doubler/amplifier.
98. 4 signals of frequencies 100,100,200 and 400 Hz are sampled at nyquist rate and sent through TDM on a channel.the bandwidth of the channel is…
99. superposition can be applied to a ckt with initial conditions/non-linear ckt/…
100. kelvin’s double bridge is used for the measurement of…
101. which of these is not an active transducer thermocouple/solar cell/RTD/none of these.
102. oscillator using positive feedback has gain of 0/∞/undefined value/…
103. wien bridge oscillator should initially have closed loop gain >3/<3/=3/…
104. some question on gain margin and phase shift of a system.
105. fourier series expansion of even function has sine terms only/cosine terms only/no odd harmonics/…
106. full wave rectifier gives clean dc o/p/dc o/p with small ripple/positive half and inverted negative half of i/p as o/p.
107. which of these values of ζ gives damped oscillations: 0/1/1.6/0.6
108. for a transformer of ratio 1:a and excited by a source V with impedances Z1 and Z2 on the primary and secondary side value of a for maxm power transfer should be..
109. fourier transform of cos(ω0t) is…
110. at t=0 the step response of a 1st order system is….
111. 555 can be used as a monostable/astable/freq dividing ckt/all of these.
112. in a PT when the secondary is open ckted with the primary excited what will happen.
113. if a system is marginally stable then the nature of oscillations will be…
114. linear encoders mostly use straight binary/BCD/gray code.
115. for an accelerometer working in displacement mode the ratio of forcing freq to natural freq should be…..
That’s all I can remember! One fact which I wish to mention is that many questions contained options which were repeated, e.g. Both a) and b) were 5. it was difficult making a choice in these cases. Aptitude(70 ques): Most of the questions were straightforward. There were questions involving profit and loss, ratio-proportion, DI from pie-charts, one RC passage and other questions from verbal. The ones involving verbal were quite confusing, as none of the options seemed to fit the question,e.g there were some questions in which you had to find the word farthest in meaning to a given word. The word given was judicious, and the options were illegal, obscure, case and some other. The same was the case with the other four questions of this sort. Overall it was an ok sort of paper, though the negligible weightage given to instrumentation related questions was somewhat surprising. NTPC PAPER ON 04th May 2008 AT KOLKATA
HI every body !!!
Recently I gave the paper of NTPC ET Recruitment from ELECTRICAL Branch the paper which included 170 questions. I attempted around 114 questions
Negative marking -1/4 th
Total questions-170 Duration - 2Hrs
Technical-120
Apti + english-50
Technical was ok and the questions mainly came from NTPC ET RECRUITMENT book published by G.K.Publishers near about 70 questions came from it. They mainly concentrated on Power Electronics. Some questions based on power system came from CL WADHWA(ELECTRICAL POWER SYSTEM). However some of the questions which came in exam are as follows.
(1)In the radial distribution system the distribution is fed from (a)both ends (b)one end (c)the centre (d)at different parts.
(2)Mho relay is used to protect (a)long transmission lines (b)medium length transmission lines. (c)short transmission lines. (d)all of these.
(3)Power can be transferred only if reactance is (a)present (b)absent (c)zero (d)none of these.
(4)Resistance switching is used in (a)minimum oil circuit breaker (b)bulk oil circuit breaker (c)oil blast circuit breaker (d)all types of circuit breaker
(5)Impulse voltages are characterized by (a)peak value (b)polarity (c)time of half the peak value (d)All of these.
(6)Back up protection is used to protect (a)Transient current (b)Short circuits (c)Over currents (d)over voltages
apti+english was simple . questions similar from gk publishers.
"ALL THE BEST FOR FUTURE ASPIRANTS"
NTPC PAPER ON 22nd APRIL AT UDAIPUR
Technical test was not so tough(Instrumentation Stream) If U prepare 2to 3 weeks sincerely U can attempt 90% of portion Paper will consist of 120 technical questions . It covers Analog,Digital,Control,Process control , Electronic Meaurement and Industrial Measurement
Qus Principle of Optical Fiber: Total Internal reflection2 Anticipatory controllers are; Derivative3 Routh Stability defines : poles on the left/right/......4. One question is on Final Value theory5 S^5+s^4+.............. : How many roots find out6 System is Marginally stable When root lies on7 One 2 question on K-Map8 9's complement of 199 encoders and Decoders are different: No of Active lines10 Flashing Memory is11 Find out Hexadecimal code of 12 Input Impedance of CRO is13 Casacading of an Low pass and high pass filter will give : Notch filter14 Pitot tube is used to measure15 Why FET is used in Electronic Voltmeter16 Data Acqsition System Comprise of Blocks: Transducers,A/d conveter, sensors...........................17 Some quetion on General Engineering18 Ph changes from 5 to 7 Hydrogen Ion concentration will increase/decrease............19 2 Questions on feedforward controlrest 50 questions of Aptitute.................
NTPC PAPER ON 22nd APRIL
Hi i wrote the NTPC exam held on april 22nd 2007 (instrumentation discipline) i would like to share syllabus&pattern of the exam .i hope that it will will b useful for future candidates. there were totally 170 ques(120 subject based que&50 aptitudue que)
time 2 hrs.
subject questions: que frm microprocessor 8085,interupts(e.g which intrpt has highest priority),address line,architecture.control systems:routh criteria,all basics.opamp,inst amplifier,inverting amplifierhexa decimal conv,BCD convmultivibrators,abt bistable multivibrator,amplitude modulation,richter scale is used to measure?bio gasinstrumentation:LVDT,strain gauge,P,I,controllers,feed forward controllers,bellows, match d following que lyk e.g
seeback effect-?piezo electric effect-?diiffrnt types of control valves,more que frm P,I ,Dcontrollers.in dp type inst ,flow is proportional to?signal conditioning,coriolis flow meter,probs based on accuracygo through all d instrumentation papers.
Aptitude:problms frm ratio,profit loss,volumes,pipes n cisterns etc.word analogies, paragraph que,fill in d most suitable type que,antonyms,synonyms
all the best
NTPC PAPER ON 22nd APRIL AT NEW DELHI HELLO frnsI am giving u the paper minutes of NTPC exam on april 22 ,2007 b’cz I have faced the problem of non availability of any pattern or sample questions .It was really an easy paper so the cut off marks r really high. It constitutes of 170 questions (120 tech + 50 apti) in 2hrs.For tech part the syllabus is same as of the GATE and for apti part R.S.Aggarwal is more than sufficient. As time duration is very short so time management is very important.
APTITUDE SECTIONFor this section no special attention is required only rs aggarwal is enough and it also has easy level of English section.
TECHNICAL SECTIONFor this section u have to b good in the basics. No hard question were asked but u should b careful about your time . It has also some part of very basic general knowledge. The questions were from following topics10-12 q about microprocessor(8085)3 q abt RS232 standard 7-10 q of GK4-6 q of opamp
10-15 q of digital comm..2-5 q of microwave15-20 q of analog devices20-23 q of digital electronics(flip flops,gates,mux,no system etc)1 q of ISO OSI model 5-8 q of control system 10-12 q of signals and their processing
SOME QUESTIONS WHICH I MANAGE TO REMEMBER1. passage for comp2. word meaning based (antonym and synonyms) fetter, fester, lucid, anomaly,
elucidate etc3. word analogy based4. what is a tunnel diode5. wht is a zener diode6. effect of + and – feedback on stability7. composition of gobar gas8. function of differential in the vehicle9. function of stack register10. fun of instruction pointer11. fun of rst6.5,7.512. wht is an interrupt13. output vtg calc on op amp14. how a pulse train can b generated using registers15. conversion of oct to hex,hex to binary16. fun of quantizer in pcm17. why fm is less prone to noise18. fun of limiter in detection of FM19. wht is envelop detector20. phase shift of 1/s^221. signal limited to 1000 hz sampled at nyquist rate.quantizer has 128 level .calculate
the bit rate of the system.22. 1.5 V battery supply same power to R1 and R2 separately(R1>R2).calc the
internal resistance of battery23. a wire is cut in two halves. one half is again stretched to th twice of length .calc
the resistance.NTPC PAPER - 09 APR 2006
I wrote the NTPC exam held on april 9th,2006(Electronics Stream)I faced the problem of "knowing the syllabus and the pattern" of it beforethe exam.I was not able to find the correct guidance in any of these grps.Soi thought I would share mine so that it would be useful for the futureaspirants of NTPC. First 120 question on technical and 50 questions on general aptitude.1/3 negative marks for all the questions.
2 hours exam.(No calculator allowed)Question paper along with the key sheet should be handed over to theinvigilator after the end of exam. About the Technical:questions about diac,triac,buck effect etc.Control systems,synchros,all basics and theoreticalcomputer NETWORKS: (abt CSMA/CD,bridges,routers,Ieee standards like 802.3,etc.(abt ethernet))VLSI (CMOS structure, functioning,)DIGITAL ELECTRONICS(gates,negative logic,postive logic,nand,counters,etc.)Sample question:write a particular number in BCD,or hex equivalent etc.)cominational circuit design(no of gates required etc.)electronics: led bias,tunnel diode bias,fet,bjt,feedback amplifierproperties,optoelectronic devices,class c amplifiers,multivibrators,band gapsin Si,Ge.,intrinsic concentration etc.general: abt ozone layer depletion (CFCs)The total efficeincy of a thermal plant.communications:Amplitude modulation,FM Vs. AM.Antennas :Director,reflector in yagi uda,microwave frequency ranges,bands,ground wave,sky wave,space wave propagation.In which media em waves travelfaster.Microprocessor 8085,interrupt structure,architecture,memories,mappingschemes,8255,interrupt controller(8259)(ICW1,OCW etc.)hard disk,floppy disk access timesmangement scienceabc analysis(inventory management)signals systems:fourier transfor,sinc functions,convolutionnetwork theory:resonant frequency formulaeOP AMPS:a/d d/a converters,differentiators and integrators,instrumentationamplifiers.digital communications:fdm, tdmI almost covered 95% of the topics.This is as far as I could remember.About aptitude:synonymsantonymscomprehension passages
aptitude problem solving skills(train probs,loss profit sums,ratios,etc.)word analogiesfill in the sentences with the most suitable word type of questions.
Tips:Time management is very important.Since most of the technical questionsare theoretical,complete them quickly and do well in the aptitude section.Individual cut off in each of the 2 sections is necessary.i don't know the actual cut off though.
