gate ece practice paper

GATECounsellor RcPP1

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EC: Electronics & Communication Engineering

Duration: Three Hours Maximum Marks: 100

Read the Instructions carefully.

1. This question paper contains 22 pages.

2. All Questions in this Paper are Objective type.

3. There are a total of 65 questions carrying 100 marks.

4. Questions 1 – 25 will carry 1-mark each, questions 26 – 55 carry 2-marks

each.

5. Questions 50 – 51 are common data questions and question pairs (52 – 53)

and (54 –55) are linked answer questions. The answer to the second

questions of the linked answer question depends on the answer to the first

question of the pair. If the first question is wrongly answered or is un-

attempted, then the answer to the second question will not be evaluated.

6. Questions 56 – 65 belong to general aptitude (GA). Questions 56 – 60 will

carry 1-mark each, and questions 61 – 65 will carry 2-marks each. The GA

questions will begin on a fresh page starting from page 20.

7. Un-attempted questions will carry zero marks.

8. Wrong answers will carry NEGATIVE marks. For Questions 1 – 25 and

Questions 56 – 60, 1/3 mark will be deducted for each wrong answer. For

Questions 26 – 51 and Questions 61 – 65,2/3 mark will be deducted for

each wrong answer.

9. The questions pairs (52 – 53), and (54 – 55) are questions with linked

answers. There will be negative marks only for wrong answers to the first

question of the linked answer question pair i.e. for Question 52 and 54, 2/3

will be deducted for wrong answer. There is no negative marking for

Question 53 and 55.


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Questions 1- 25 carry 1 Mark each.

1. What is the relation between for matrix B with rank of order 3,

(a) (c)

(b) (d) All of the above

2. is a linear equation if

(a)

(b)

(c) and both are constant

(d) and constant

Where means function of .

3. Which of the following is true?

1. , where

2. , provided and

3.

(a) All of the above

(b) Only 1

(c) Only 2

(d) Only 1 and 2

4. In a Zener diode

(a) Both and sides are lightly doped

(b) Both and sides are heavily doped

(c) side is heavily doped than side

(d) side is heavily doped than side

5. A junction diode has and . The voltage

required to align the conduction bands of both sides to same level is,

(

(a) 0.31 V

(b) 0.41 V

(c) 0.64 V

(d) 0.82 V


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6. Which of the following is NOT a property of cumulative distribution function(CDF)?

(a) (c) is right-continous (b) is monotonically increasing

function

(d)

7. The condition H(ω + ωc)+ H(ω - ωc) = constant in Vestigial Side Band Modulation is

required for:

I. Distortion-less detection II. Easy filter design

III. Necessary for synchronous detection Which of the following option is true?

(a) I only (c) All of these

(b) I and II (d) I and III

8. The modulation index of a frequency modulated wave depends on:

m(t) = message signal

I. Amplitude of m(t) II. Frequency of m(t)

III. Phase of m(t)

(a) All (c) II, III

(b) I, II only (d) I only

9. In a PCM system, the step-size is 2V. If the step-size is reduced to 0.25V, the

quantization noise power decreases by a factor of:

(A) 4 (B) 16 (C) 32 (D) 64

10. Match the list

A. TTL

B. ECL

C. MOS

D. CMOS

1. Low Propagation Delay

2. Low power Consumption

3. High packing density

4. Saturated bipolar logic

(a) A-4, B-1, C-3, D-2

(b) A-4, B-3, C-2, D-1

(c) A-4, B-3, C-2, D-1

(d) A-3, B-1, C-4, D-2


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11. In the following figure, G will be given by,

(a)

(b)

(c)

(d)

12. The following figure shows the memory map of an 8085 Microprocessor based

design. Identify the values of w, x and y respectively. (w, x and y are ending

addresses of the blocks)

(a) 1000 H, 4000 H, 1000 H

(b) 0FFF H, 4FFF H, 5FFF H

(c) 1000 H, 5000 H, 6000 H

(d) 0FFF H, 3FFF H, 0FFF H

13. In the circuit shown below, an ideal diode is used with cut-in voltage The

transfer function of the circuit is:

R S T

R

S

P

T

T G


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(a)

(c)

(b)

(d)

14. In a half wave rectifier, the rms value of current for input voltage is

(R is the resistance value in ohms and consider ideal diode):

(a)

(b)

(c)

(d)

15. An air filled rectangular waveguide has dimensions 7cm 3.5cm, the ratio of cutoff

frequencies in TE01 mode to that in TE10 mode is

(a) 1/2

(b)

(c) 1

(d) 2

16. An end fire array consisting of several half wavelength long isotropic radiator is to

have a directive gain of 30. Beam width between first null is given by

(a)

(b)

(c)

(d)

R

VR


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17. A lossless transmission line of length is short circuited at one end. The impedance

measured at the other end is at a frequency of 13.5MHz. If the frequency is raised

to 27MHz the impedance measured would be

(a)

(b) –

(c) 0

(d)

18. If is as shown in the following figure,

Sketch ,

(a)

(c)

(b)

(d)

19. Match the following.

I II

(I) A. 0

(II) (sin5 ) ( )t t B. ( )t

(III) (cos5 ) ( )t t C. 7.51 3

4 2e t

(IV) (sin5 ) (5 )t t D. 30 ( 4 6)e t

E. 5 ( )t

(a) I– C, II – A, III – B, IV – A

(b) I – D, II – A, III – B, IV – A

(c) I – C, II – E, III – B, IV – B

(d) I – D, II – E, III – B, IV – B

-2 -1 1 2 3


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20. Find the Fourier Transform of 3 ( 2).te u t

(a)

(b)

(c) 2( 3)

3

je

j

(d) 2( 3)

3

je

j

21. A system with the TF, has an output for the input

signal . Then the system parameter ‘ ’

22. In the root locals for open loop TF , the break points are

located respectively at

(a) -1.26,-3.66 (c) -1.46, -3.86

(b) -1.36, -3.76 (d) None

23. The state matrix to the given block diagram is

(a)

(b)

(c)

(d)


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24. The circuit shown below is RC circuit. The rate of increase of voltage across C at the

instant just after the switch is closed (i.e. at ) will be

(a) Zero

(b) Infinity

(c) RC

(d)

25. and are shown in Figure. The current source Ampere.

Determine , , if the switch is moved to position 2, at

after staying a long time in position 1.

(a) -5.11 V/s2, 4 A/s, 3.75 V

(b) -8.11 V/s2, 7 A/s, 3.75 V

(c) -4.44 V/s2, 4 A/s, 3.7 V

(d) -6.44 V/s2, 7.5 A/s, 7.5 V

Questions 26- 55 carry 2 Marks each.

26. For what value of , the following velocity function is a Solenoidal Vector function

(a) 11/3

(b) 10/3

(c) 2

(d) -11/3

27. Find the residue of

(a)

(b)

(c)

(d) None of these


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28. the value of would be

(a) 0

(b) 1

(c)

(d)

Where is constant

29. Find the root of equation by Regula Falsi method in 3 steps,

(a) 2.47

(b) 2.74021

(c) 2.0741

(d) 2.427

30. If are Zener and Avalanche break down voltages and & are electric

fields required to cause the breakdown respectively, then

(a)

(b)

(c)

(d)

31. A BJT has doping levels in emitter, base and collector such that

, then which of following diagram shows the correct position and

width of the depletion regions (shaded in figure) are the two depletion

region at base emitter and base collector junctions respectively.

(a)

(b)

(c)

(d)


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32. Suppose a T1 carrier system is used to multiplex 24 independent voice inputs based

on an 8-bit word. The necessary transmission bandwidth by using a full-cosine roll-

off with will be:

(a) 0.647 MHz (b) 1.54 MHz (c) 1.5 MHz (d) 0.7 MHz

33. If scaling factor = 1, output i.e. y(t) will be:

34. All the elements has delay time of 100pico second. What is the fundamental

frequency at the output is,

(a) 1.66GHz

(b) 1.33GHz

(c) 1.66MHz

(d) 3.33GHz

(a) (b)

(c) (d)


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35. The frequency of the pulse at output is in the combination of counter shown below

A. 1MHz

B. 100KHz

C. 0.5MHz

D. 50KHz

36. Consider the following sequence of instruction for an 8085 µP :

EI

MVI A, 2AH

SIM

After the execution

(a) Serial output & RST6.5 are disabled, RST7.5 & RST5.5 are enabled

(b) Serial output & RST6.5 are enabled, RST 7.5 & RST5.5 are disabled

(c) Serial output, RST7.5 & RST5.5 are disabled, RST 6.5 is enabled

(d) Serial output, RST7.5 & RST5.5 are enabled, RST 6.5 is disabled

37. A bypass capacitor is used in biasing in order to

(a) Improve ac response

(b) Improve dc response

(c) Improve both ac & dc response

(d) None of above

38. Out of following biasing techniques, the one which provides least sensitivity in

collector current with respect to β is,

(a) Fixed bias

(b) Emitter bias

(c) Voltage divider bias

(d) Feedback bias

39. If a transmission line of 50Ω characteristic impedance is terminated with a 100Ω

resistance, the minimum impedance measured on the line is

(a) 0Ω

(b) 25Ω

(c) 50Ω

(d) 100Ω

5 BIT RING

COUNTER

2 BIT

PARALLEL

COUNTER

MOD 5

RIPPLE

COUNTER

5 BIT

JOHNSON

COUNTER INPUT OF

1MHz Y


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40. A plane wave whose electric field is given by passes

normally from a material ‘A’ having and to material ‘B’ having

and . Match the list I to list II and select the correct answer

using the code given below this,

List I

A) Intrinsic impedance of B

B) Reflection Coefficient

C) Transmission Coefficient

D) Phase shift constant of A

List II

1.

2.

3.

4.

A B C D

(a) 4 1 2 3

(b) 2 3 4 1

(c) 4 3 2 1

(d) 2 1 4 3

41. The pole–zero plot of the TF of a linear time invariant system in s-plane is

shown in the figure. The corresponding impulse response is sampled at 3Hz

to get the discrete–time impulse response sequence ,

If the Right Hand side plane of the s-plane is mapped on outside of the unity circle

which one of the following pole-zero plot in z plane gives ,


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(a) (c)

(b) (d)

42. Find the Laplace Transform of ( )n att e u t with ROC.

(a) 1

!,

( )n

nS a

s a

(c)

(b) (d)


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43. Find the circular convolution of & .

1 2[ ] 2,1,3, 4, [ ] 1,3, 5, 7x n x n

(a) 36, 6,44,14

(b) 2, 5,16,14, 34, 1,28

(c) 2, 5,16,14

(d)-36,-6,16,14

44. For the given Nyquist plot the Open Loop system is stable,

and then the range of values for

Closed Loop system stability is

(a)

(b)

(c)

(d)

45. Given the plant shown in the figure below, the relationship between & to make

the system uncontrollable is

(a)

(b)

(c)

(d)


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46. Match the following Time domain specifications to the given poles path in the

plane,

I. Time domain specifications

i. system becomes less stable.

ii. No effect on Stability.

iii. have slight-variations, system becomes

more stable.

iv. has slight-variations, system becomes more

stable.

II. Pole Moment

A A.

C.


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(a)

(b)

(c)

(d)

47. The network has its T parameters as . Find T parameters of X.

(a)

(b)

(c)

(d)

B.

D. Semicircular moment of poles


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48. The 2-Dimensional network of the figure consist of an infinite number of square

meshes each side of which has a resistance of . Find the effective resistance

between two adjacent nodes such as .

(a)

(b)

(c)

(d) R/8

49. The variation of and with f is shown in figure, the value of f at

which the reactive part stops taking energy from energy source is,

(a)

(b)

(c)

(d)


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Common Data Questions:

Common Data Questions 50 and 51:

50. In this circuit, the small signal gain is

(a) -7.8

(b) -12.4

(c) -10.3

(d) -14.6

51. For previous question, are

(a)

(b)

(c)

(d)

Linked Questions

Statement for Linked Answer Questions 52 and 53.

A p-n junction diode has the difference of doping concentrations given by

, where constant and is length along the diode as shown.


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52. The magnitude of maximum electric field in depletion region is given by

(a)

(b)

(c)

(d)

( is permittivity of diode material)

53. For previous question, the built in potential is

(a)

(b)

(c)

(d)

Statement for Linked Answer Questions 54 and 55.

Let the probability of a discrete memory-less source be given by:

0.4 0.2 0.2 0.1 0.1

54. Average code word length will be:

(a) 2.1 (b) 2 (c) 2.2 (d) Data insufficient

55. The coding efficiency will be:

(a) 0.9 (b) 0.34 (c) 0.96 (d) 0.1


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General Aptitude (GA) Questions

Questions 56 - 60 carry one mark each.

56. The question below consists of a pair of related words followed by four pairs of words.

Select the pair that best expresses the relation in the original pair.

INTIMATE : CLOSE

(A) evanescent : permanency

(B) articulate : speech

(C) enclose : parentheses

(D) obsessed : attracted

57. In the following question, a word is given in bold which precedes four more words. Pick

the word from the four options which most nearly opposite in meaning to the bold

word.

POLEMICAL

(A) lavish (B) imitative (C) conciliatory (D) attractive

58. Which of the following options is the closest in meaning to the word below:

DELETERIOUS

(A) delaying (B) glorious (C) harmful (D) graduating

59. In the following question one word-part is given with example, followed by four

options. Choose the most appropriate word which best describes the usage of the given

word-part in a word.

dis- (Ex. disperse)

(A) free, book (B) not, apart (C) before (D) obsession

60. Find the unit’s digit in the product 24647117 and 4563124647

(A) 9 (B) 7 (C) 3 (D) 1


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Questions 61 - 65 carry two marks each.

61. The recent news that local hospitals have had to reroute seriously ill patients because the community's critical-care beds are full is worrisome. Earlier this week, four of the six local hospitals ran out of space for the critically ill and had to turn people away. Federal law requires hospitals to treat anyone who walks in. As a result of having to treat large numbers of uninsured patients, the emergency rooms often become an economic drain on their hospitals. Doctors now want to set up their own free standing ambulatory surgical facilities and diagnostic centers. Critics contend this would leave hospitals with less revenue and the same number of indigents to treat. A bill was recently introduced to phase out the need for a "certificate of public need" for non-hospital based facilities, provided those facilities met stringent regulations and requirements. This would have made it easier to set up alternative facilities to help indigent patients. The finance committee balked at the hefty price and killed the bill, another casualty of a failed legislative session. Unfortunately, the problem of access to medical care for those of limited means is not going to go away anytime soon and, despite the well-intended regulations, too-full hospitals compromise everyone's welfare. Healthy competition with small neighborhood surgical and diagnostic centers may be what is necessary to help dampen rising medical costs. But under no circumstances should the hospitals be forced to care for everybody without health insurance while competitors operate free of the burden of caring for those unable to pay.

According to the passage, which of the following is cited as a factor which has contributed to the overburdening of hospitals?

I. Failure to pass legislation which would have mitigated the problem II. Limited access to medical care for the poor

III. Federal law

(A) I only

(B) III only

(C) I and II

(D) I, II, and III

62. Ram and Hari started from A and B, towards B and A at 6.00 am and 7.00 am

respectively. They meet each other at 9.00 am and continued towards their respective

destinations. Ram reaching B turns back and catches up with Hari before Hari reaches A

at 11.00 am. At what time will Hari reach A.

(A) 7.00 pm (B) 4.00 pm (C) 5.00 pm (D) 6.00 pm


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63. A person has the capability of thinking 100 lines of code in five minutes and can type

100 lines of code in 10 minutes. He takes a break for five minutes after every ten

minutes. How many lines of codes will he complete typing after an hour?

(A) 100 (B) 250 (C) 350 (D) 600

64. A solid, four-inch cube of wood is coated with blue paint on all six sides. Then the cube

is cut into smaller one-inch cubes. These new one-inch cubes will have either three blue

sides, two blue sides, one blue side, or no blue sides. How many of two side colored will

there be?

(A) 24 (B) 8 (C) 16 (D) 12

65. One of twelve pool balls is a bit lighter or heavier (you do not know) than the others. At

least how many times do you have to use an old balance-type pair of scales to identify

this ball?

(A) 1

(B) 3

(C) 7

(D) 12

END OF THE QUESTION PAPER


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gate ece practice paper

Documents

linked answer questions

questions pairs

ga questions

doped c

doped b

matrix b

constant d

continous b