Electrical Engineering

Mock Test-1 Full Name of the Student________________________________________________________

Mobile No. ___________________________________________________________________

NOTE: This question paper consists of 2 sections, General Aptitude (GA) for 15 marks

and the subject specific GATE paper for 100 marks. Both these sections are

compulsory. The GA section consists of 10 questions. Question numbers 56 to 60 are

of 1-mark each, while question numbers 61 to 65 are of 2-mark each. The subject

specific GATE paper section consists of 55 questions, out of which question numbers

1 to 25 are of 1-mark each, while question numbers 26 to 55 are of 2-mark each.

All questions that are not attempted will result in zero marks. However, wrong

answers for multiple choice type questions (MCQ) will result in NEGATIVE marks.

For all MCQ questions a wrong answer will result in deduction of⅓ marks for a 1-

mark question and ⅔ marks for a 2-mark question. There is NO NEGATIVE

MARKING for questions of NUMERICAL ANSWER TY

Technical Section Q.1 – Q. 25 carries one mark each

1) For the following circuit, equivalent Norton current and resistance (IN , RN) are

a) 2A, 20 b) 2 A, - 20

c) OA, 20 d) OA, - 20

2) A Certain network consist of a large number of ideal linear resistors, one of which is

R and two constant ideal source the power consumed by R is P1 when only the first source

is active, and P2 WHEN only the second source is active. If the sources are active

simultaneously then power consumed by R is

a) 1 2P P b) 1 2P P

c) 2

1 2P P

d) 2

1 2P P

3) In the circuit shown below. The switch is opened at t = o+, the value of 2

2

( )Rd V t

dt

a) – 1010 V /s2 b) 1010 V/s2

c) 1013 V/s2 d) – 1013 V/s2

4) The switch in the given circuit has been closed for a long time and opens at t = 0 the

rate of change of voltage (0 )Ldv

isdt

a) O b) sV

R C

1

c) 1 2( )

sC

V

R R d)

2

sV

R C

5) In the given circuit, node voltage V2 at steady state is -----volts.

6) For a negative feedback system shown below G (s) = 1 3

, ( )( 2) 4

s sH s

s s s

The equivalent transfer function is

a) 2 2

( 2)( 3)

7 12 3

s s s

s s s

b)

2 2

( 2)( 3)

5 4 3

s s s

s s s

c) 3 2

( 1)( 40

7 12 3

s s

s s s

d)

3 2

( 1)( 4)

5 4 3

s s

s s s

7) The overall transfer function for the system shown below is

a) G b) 21

G

H

c) 1 2)(1 )(1

G

H H

d) 2 21

G

H H

8) The forward path transfer function of a ufb system G (s) = 2

2

( 4)

3

K s

s

The system is stable for

a)K > - 1 b) K < 0.75

c) -1 < k < 0.75 d) Unstable

9) The location of poles on RHP, LHP, and axis for the open loop system with transfer

function 2

4 2 2

5 6( )

4 8 20 15

s sG s

s s s

is

a) 2, 2, 0 b) 0, 2, 2

c) 2, 0, 2 d) None

10) For a second order control system defined by 2

2

( ) ( )4 8 16 ( ) 16 ( )d c t dc t

c t r tdt dt

the

damping ratio and natural frequency are

a) 0.5 & 2 rad/s b) 0.05 and 2 rad/s

c) 0.25 & 2 rad/s d) 0.5 and 4 rad/s

11) A 3 phase star connected synchronous generator rated at 20 kVA and 230V has a

synchronous reactance of 1.2 ohms per phase and an armature resistance of 0.5 ohm per

phase. Calculate the percentage voltage regulation at full load with 0.8 lagging power factor

a) 44.51% b) 22.5%

c) 89.1% d) 21.51%

12) A 240V, DC series motor takes 20A when giving its rated output at 1500 rpm. The

resistance which must be added in series with armature to obtained rated torque at 1000

rpm

a) 3.9 b) 1.9

c) 2.9 d) 4.9

13) A 4 pole series motor have wave wound armature with 300 conductors. Total

resistance is 0.8 when fed form 250V, dc motor supplier a load of 10 kW takes 50A with

a flux of 3 mwb. Determine developed torque and shaft torque

a) 14.33 N-m, 13.648 N-m b) 12.33 N-m, 11.22 N-m

c) 11.33 N-m, 16.648 N-m d) 14.14 N-m, 13.648 N-m

14) The external load characteristics of a dc generator at rated speed is assumed to the

linear and is as shown in figure. The load circuit comprises only resistance when the load

current is 50 A the value of the load circuit resistance will be

a) 2.2 b) 1.1

c) 1.9 d) 3.4

15) A permanent magnet dc commutator motor has no load speed of 3000 rpm. When

connected to 120 V dc supply. The armature resistance is 1.5 and other losses may be

neglected. The speed of the motor with supply voltage of 60 V when developing a torque

0.5 Nm is

a) 145.875 rpm b) 1250.845 rpm

c) 2901.75 rpm d) 1350.875 rpm

16) On the line described by x = 2 m, y = - 4 m there is a uniform charge distribution of

density /nC m 1 10 . Determine the electric field E

at

( , , ) .m 2 1 4

a) ˆ ˆx ya a 4 3

b) ˆ ˆ. .x ya a 28 8 21 6

c) ˆ ˆx ya a 4 3

d) ˆ ˆ. .x ya a 57 6 4 32

17) As shown in figure two uniform line charges of density /l nC m 4 lie in the x = 0

plane at y = m4 . Find E at (4, 0, 10) m

a) ˆxa9 b) ˆya18

c) ˆya9

d) ˆxa18

18) A uniform sheet charge with ( / ) /s nC 1 3 m2 is located a z = 5 m and a uniform

line charge with ( / )l 25 9 nC / at z = -3 m, y = 3m. Find E at (x, -1, 0) m

a) ˆ ˆy xa a8 8

b) ˆ ˆx za a8 12

c) ˆ ˆz za a8 16 c) ˆ ˆz za a8 12

19) charge lies on the circular disk r 4 m, z = 0 with density ( / ) ( / )s r C m 4 210

determine E at r = 0, Z = 3 m.

a) ˆ. /za MV m15 1 b) ˆ. /za MV m1 51

c) ˆ. /za MV m2 7 d) ˆ. /za MV m2 7

20) Change lies in the z = -3 m plane in the form of a square sheet defined by

,x m y m 2 2 2 2 With charge density /( ) /s x y nC m 2 2 3 2 22 9 . Find E on the

side of the plane containing the origin

a) ˆ /za V m108 b) ˆ /za V m216

c) ˆ /za V m432

d) ˆ /za V m864

21) A voltmeter having a sensitivity of 1 k /V is connected across anun known resistance in series with a milli-ammeter reading 80 V on 150 V scale. When the milli-ammeter draws 10 mA current, find the error due to the loading effect of the voltmeter (Neglect the resistance of the milli-ammeter) a) -4.3% b) -5.3% c) -6.3% d) -7.3% 22) Design a universal shunt meter with current ranges of 10 mA and 50mA; With a d.c. ammeter of internal resistance 100 and full scale current of 100 A. If R1 and R2 are

resistances required then sum of R1and R2 is a) 1.212 b) 1.312 c)1.412 d) 1.512 23) When a sinusoidal signal of 220 V, 50 Hz on CRO produces a vertical deflection of 2 cm at a particular setting of the vertical gain control, what would be the value of the voltage to be applied to produce a deflection of3 cm for the same vertical gain? a) 330 V b) 110 V c)220 V d) 55 V 24) An analog voltage signal whose highest significant frequency is 1 kHz is to be coded with a resolution of 0.01 percent for a voltage range of 0-100V. The minimum sampling frequency and the minimum number of bits should respectively be a) 1 kHz and 12 b) 1 kHz and 14 c) 2 kHz and 12 d) 2 kHz and 14

25) The figure shows the circuit of a rectifier type voltmeter.

The diode D2 1. Does not allow any current to flow through meter during negative half cycle. 2. Does not allow reverse leakage current to flow through the meter during negative half cycle. 3. Short circuits the meter during negative half cycle. Which of these statements are correct? a) 1 and 2 only b) 2 and 3 only c) 1 and 3 only d) 1, 2 and 3 26) Which of the following plant has least running cost?

a) Diesel power plant b) Nuclear power plant

c) Thermal power plant d) Hydro-electric power plant

27) Sag of conductors between any two poles can be determined by

a) 2WL

T b)

2

2

WL

T

c) 2

8

WL

T d)

2

16

WL

T

28) The incremental cost curves in Rs/mwhr for two generators supplying a common

load of 700 mw are shown in the figure. Incremental cost Rs/mwhr

a) A: 400 MW, B: .300 MW b) A 350 MW, B: 350 MW

c) A: 450 MW B: 250 MW d) A: 425 MW B: 275 MW

29) Corona helps in avoiding

a) Electrostatic stresses between the conductors

b) Effect of lightning

c) Effect of surges on the transmission line

d) All of the above

30) when moisture content in air increases the disruptive critical voltage will

a) Increase b) Decrease

c) Remain constant d) Can’t say

31) Let y [n] = x [n] * h [n], then x [x – n1] * h [n-1] equal * to

a) y [ n – n1 +n2] b) Y [n + n1+n2]

c) Y [n – n1 – n2] d) Y [n + n1-n2]

32) The ROC of Laplace transform of the CT single x (t) = 3 exp 9-2t) 4 (t) + 4 exp (t) u (-

t) is

a) -1 < Re (s) < 2 b) -2 < Re (s) < 1

c) 1 < Re (s) < 2 d) 0 < Re (s) < 2

33) A Caural LTI system with a proper rational transfer function H(s) is stable if and

only if

a) Polar of H (s) lies in the left half of s-plane

b) Poles of H(s) lie in the right half of the s-plane

c) At least one pole lies at origin.

d) None of these

34) Of a signal x (t) is of finite duration and is absolutely integrable, then the ROC of its

Laplace transform is

a) A single strip b) Entire s-plane

c) Entire right half of s-plane d) Entire left half of s-plane

35) The z-transform of a single x [n] is z 1/zX z e e , . ( )z x n0 would be

a) !

nn

1

b) !n n 1

c) u n 1 n !

d) !n n 1

36) An amplifier has a gain of 1000 10 .Negative feedback is provided such that gain variation is within 0.1% .Then the amount of feedback f is

a) 1

10 b)

1

9

c) 9

100 d)

9

1000

37) A transistor with =49 and Ico= ICB0= 1A has IB=10A the value of Ic is given in

A by a) 441 b) 490 c) 539 d) 540 38) In a transistor having finite ; the forward bias across the base emitter junction is

kept constant and the reverse bias across the collector base junction is increased neglecting the leakage across the collector base junction and the depletion region generation current, the base current will a) Increase b) Decrease c) Remain constant d) Cannot be predicted 39) An amplifier has a power gain of 50. This gain in dB will be a) 17dB b) 31 dB c) 34 dB d) 68 dB

40) Negative feedback in amplifiers a) Improves the signal to noise ratio at the i/p b) Improves the S/N ratio at O/P c) Does not affect S/N ratio at O/P d) Reduces distortion 41) The thermal resistance between the body of a power semiconductor device and the ambient is expressed as a) Voltage across the device divided by current through the device. b) Average power dissipated in the device divided by the square of rms current in device. c) Average power dissipated in the device divided by the temperature difference from body to ambient d) Temperature difference from body to ambient divided by average power dissipated in the device. 42) Analysis of voltage waveform of a single-phase bridge converter shows that it contains x% of 6th harmonic. The 6th harmonic content of the voltage waveform of a 3-phase bridge converter would be a) difficult to predict as the analysis of converters is not governed by anygeneralized theory. b) less than x% due to an increase in the number of the single phase converter. c) equal to x%, the same as that of the single-phase converter. d) greater than x% due to changes in the input and output voltages of the converter. 43) In the circuit shown below,

If load R = 500 Ω, switching frequency is 25 kHz and peak to peak ripple current of inductor is limited to 0.8 A then the filter inductance L is a) 121.62 μH b) 145.83 μH c) 136.24 μH d) 151.4 μH

44) Match List-I (Chopper configurations) with List-II (Output voltage waveforms) and give the correct answer by using the codes given below:

A. Voltage-commuted chopper

B. Load-commuted chopper

C. current commuted chopper

D. ideal DC chopper

Codes: A B C D a) 2 4 1 3 b) 2 4 3 1 c) 4 2 1 3 d) 2 1 4 3 45) In the half-bridge inverter of figure, main thyristorT1 is conducting a load current.

With polarity of the capacitor voltage as shown, when auxiliarythyristorTA1 is turned-on, capacitor current ic 1. Would flow through D1, because capacitor voltage Vc forward biases diode D1. 2. Cannot flow through D1, because voltage drop across T1 reverse biases D1. 3. Cannot flow through T1, because thyristor is unidirectional device 4. Would flow through T1, such that load current minus I cflows that from anode to cathode. From these, the correct statements are: a) 1 and 3 b) 2 and 4 c) 3 only d) 4 only

46) The coefficient of rank correlation between marks in statistics and marks in

mathematics by a certain group of student is 0.8 if the sum of the squares of the difference

in rank is given to be 33, the number of students in the group _____

a) 15 b) 10

c) 20 d) 25

47) The transcendental equation of the following

(i) x x 3 0

(ii) x4 – x3 + x2 – x +1 = 0

(iii) x – cos x = 0

a) i) b) (ii)

c) (iii) d) None of these

48) If a matrix has 72 elements, then number of possible dimension will be _______

49) The value of 1 z x z

1 0 x z

(x y z) dx dydz

________

a) 1 b) -1

c) 2 d) 0

50) The value of the integral 1 i 2 2

z 0(x y )dx 2x dy

along y = x2 is

a) 0 b) 4

5

c) 4

5 d)

4

15

51) The effective temperature of a body having an area of 0.12 m2 is 5270C . What is the

total rate of energy emission and intensity of normal radiation?

a) 2787 W, 7392 W/m2

b) 2.78 kW, 9.5 2kW / m

c) 2531 W, 6342.2 W/m2

d) 6431 W, 7392.5 w/m2

52) The equation of motion for a single degree of freedom system with viscous damping

is 4x 9x 16x 0 the damping ratio of system is _____

53) Two bodies of mass m1 and m2 are dropped from different heights h1 and h2

respectively. Neglecting the effect of friction, the ratio of times taken to drop through given

heights would be

a) 1

2

m

m b) 1 1

2 2

m h

m h

c)

0.5

1

2

h

h

d)

2

1

2

h

h

54) The probability that a managed 60 will live to be 70 is 0.6 what is the probability

that out of 9 men 60 exactly 5 will live to be 70?

a) 0.63 b) 0.54

c) 0.30 d) 0.72

55) The following are the available data of sales in lakhs of rupees:

Year 1980 1981 1982 1983 1984

Sales 50 70 60 80 90

Assuming the same relationship hold true for future the sales forecast for the year 1990 by

applying least square method (in lakhs) is _______

General Ability

# Q 56 to 60 One Marks

56) The old woman was ancient, dispirited and _______, and she breathed with a rasping

sound that suggested every breath, even when seated, was a monumental effort.

a) Brawny b) Emaciated

c) Breviloquent d) Devious

57) After lecturing for two hours, harry finally managed to ______an answer from the

listless audience

a) Elicit b) Fortify

c) Illicit d) Avenge

58) The first agitation on that subjected had begun in 1906, by two sportsmen whose

names in connection with it have long since been forgotten

a) In connection with it have long been forgotten.

b) I connection with it have since long been forgotten

c) In connection with it have long since had been forgotten

d) In connection with it have long since been forgotten

59) A boat running upstream takes 8 hours 48 minutes to cover a certain distance,

while it takes 4 hours to cover the same distance running downstream. What is the ratio

between speed of the boat and speed of the water current respectively?

a) 2:1 b) 3:2

c) 8:3 d) 4: 3

60) Choose the word which is most nearly the same in meaning as the word given in

bold as used in the passage

CONVOLUTED

a) Bombastic b) Erudite

c) Politic d) Intricate

Q. 61 to Q. 65 Two Marks

61) A metallic sheet is of rectangular shape with dimensions 48 m x 36 m. from each of

its corners, a square is cut off so as to make an open box. If the length of the square is 8 m,

the volume of the box (in m3) as is

a) 4830 b) 5120

c) 6420 d) 8960

62) Sakshi invests a part of Rs 12, 000 in 12% stocks at Rs 120 and the remainder in

15% stocks at Rs 125. If his total dividend per annum is Rs 1360, how much does he invest

in 12% stock at Rs 120?

a) Rs 4000 b) Rs 4500

c) Rs 5500 d) Rs 6000

63) choose the option that best captures the essence of the given text The nineteenth

century had been pre-eminently an era of the development of rapid and easy

communication between distance parts of the world, particularly between distance parts of

the world, particularly between Europe and Asia. So long as these two continents remained

far apart the condition of Asia was unchanged and stationary; if there was any change it

had been latterly retrogressive, for in India at any rate the eighteenth century was a period

of abnormal and extensive political confusion. In Europe, on the other hand, national

wealth, scientific discoveries, the arts of war and peace, had made extraordinary progress.

Population had increased and multiplied; and partly by territorial conquest, partly by

pacific penetration the western nations overflowed politically into Asia during the

nineteenth century

a) The ninetieth century marked the beginning of tremendous progress in communication

and technology which helped link Asia and Europe.

b) Asia was unchanged till the invention of communication devices and dependent on

Europe for a change in the ongoing retrogressive state

c) The political confusion in India in the eighteenth century and the breakthrough in

science and the general progress in Europe were in stark contrast that led to penetration of

Europeans into Asia

d) There was a great difference in the progress levels of Europe and Asia; Asia was largely

unchanged but subsequently the population of Asia multiplied due to entry of the Western

nations.

64) From a point P on a level ground, the angle of elevation of the top tower is 300. If the

tower is 100 m high, the then the distance (in m) of point P from the foot of the tower is

_____

65) The following pie-chart shows the source of funds to be collected by the National

Highways Authority of India (NHAI) for its phase II projects. Study the pie-chart and

answer the question that follows:

Source of funds to be arranged by NHAI for phase II projects (in crores Rs)

Near about 20% of the funds are to be arranged through

a) SPVS b) External assistance

c) Annuity d) Market borrowing