GATE ECE 2012
View Questions

GATE ECE

1
The diodes and capacitors in the circuit shown are ideal. The voltage v(t) across the diode D1 is GATE ECE 2012 Analog Circuits - Diodes Question 17 English
2
The current ib through the base of a silicon npn transistor is $$1\;+\;0.1\;\cos\left(10000\;\mathrm\pi\;\mathrm t\right)$$ mA . At 300 K, the $$r_\mathrm\pi$$ in the small signal model of the transistor is GATE ECE 2012 Analog Circuits - Bipolar Junction Transistor Question 53 English
3
The voltage gain Av of the circuit shown below is GATE ECE 2012 Analog Circuits - Bipolar Junction Transistor Question 25 English
4
The circuit shown is a GATE ECE 2012 Analog Circuits - Operational Amplifier Question 33 English
5
A source alphabet consists of N symbols with the probability of the first two symbols being the same. A source encoder increases the probability of the first symbol by a small amount $$\varepsilon $$ and decreases that of the second by $$\varepsilon $$. After encoding, the entropy of the source
6
In a base band communications link, frequencies up to 3500 Hz are used for signaling. Using a raised cosine pulse with 75% excess bandwidth and for no inter-symbol interference, the maximum possible signaling rate in symbols per second is
7
Two independent random variable X and Y are uniformly distributed in the interval [ - 1, 1]. The probability that max [X, Y] is less than 1/2 is
8
The power spectral density of a real process X(t) for positive frequencies is shown below. The value of $$E\,\left[ {{X^2}\,(t)} \right]$$ and $$E\,\left[ {X\,(t)} \right]$$, respectively, are GATE ECE 2012 Communications - Random Signals and Noise Question 18 English
9
A BPSK scheme operating over an AWGN channel with noise power spectral density of N02, uses equi-probable signals $$${s_1}\left( t \right) = \sqrt {{{2E} \over T}\,\sin \left( {{\omega _c}t} \right)} $$$
and $$${s_2}\left( t \right) = - \sqrt {{{2E} \over T}\,\sin \left( {{\omega _c}t} \right)} $$$

over the symbol interval, $$(0, T)$$. If the local oscillator in a coherent receiver is ahead in phase by 450 with respect to the received signal, the probability of error in the resulting system is

10
A binary symmetric channel (BSC) has a transition probability of 1/8. If the binary transmit symbol X is such that P(X =0) = 9/10, then the probability of error for an optimum receiver will be
11
The signal m(t) as shown is applied both to a phase modulator (with kp as the phase constant) and a frequency modulator (with kf as the frequency constant) having the same carrier frequency. GATE ECE 2012 Communications - Analog Communication Systems Question 8 English

The ratio kp/kf (in rad/Hz) for the same maximum phase deviation is

12
The feedback system shown below oscillates at 2 rad/s when GATE ECE 2012 Control Systems - Stability Question 11 English
13
A system with transfer function g(s) = $${{\left( {{s^2} + 9} \right)\left( {s + 2} \right)} \over {\left( {s + 1} \right)\left( {s + 3} \right)\left( {s + 4} \right)}},$$ is excited by $$\sin \left( {\omega t} \right).$$ The steady-state output of the system is zero at
14
The transfer function of a compensator is given as $${G_C}(s) = {{s + a} \over {s + b}}.$$

The phase of the above lead compensator is maximum at

15
The transfer function of a compensator is given as $${G_C}(s) = {{s + a} \over {s + b}}.$$

$${G_C}(s)$$ is a lead compensator if

16
The state variable description of an LTI system is given by GATE ECE 2012 Control Systems - State Space Analysis Question 22 English

where y is the output and u is input. The system is controllable for

17
The state transition diagram for the logic circuit shown is GATE ECE 2012 Digital Circuits - Sequential Circuits Question 34 English
18
The output Y of a 2-bit comparator is logic 1 whenever the 2-bit input A is greater than the 2-bit input B. The number of combinations for which the output is logic 1, is
19
Consider the given circuit. In this circuit, the race around

GATE ECE 2012 Digital Circuits - Sequential Circuits Question 53 English
20
The magnetic field along the propagation direction inside a rectangular waveguide with the cross section shown in the figure is $${H_Z} = 3\,\,\cos \,\,(2.094\,\, \times \,\,{10^2}x)\,\,\,\cos \,(2.618\,\, \times \,\,{10^2}y)$$
$$\cos \,\,(6.283\,\, \times \,\,{10^{10}}t\, - \beta \,z)$$
The phase velocity $${V_p}$$ of the wave inside the waveguide satisfies GATE ECE 2012 Electromagnetics - Waveguides Question 23 English
21
A coaxial cable with an inner diameter of 1 mm and outer diameter of 2.4 mm is filled with a dielectric of relative permittivity 10.89. Given $${\mu _0} = \,4\,\pi \, \times \,{10^{ - 7}}$$
$$H/m,\,\,{\varepsilon _0} = {{{{10}^{ - 9}}\,} \over {36\,\pi }}\,F/m,$$ the characteristic impedance of the cable is
22
The electric field of a uniform plane electromagnetic wave in free spce, along the positive x direction, is given by $$\vec E = 10\left( {{{\widehat a}_y} + j{{\widehat a}_z}} \right){e^{ - j25x}}.$$ The frequency and polarization of the wave respectively are
23
A plane wave propagating in air with $$\vec E = \left( {8{{\widehat a}_x} + 6{{\widehat a}_y} + 5{{\widehat a}_z}} \right){\mkern 1mu} {\mkern 1mu} {e^{j\left( {\omega t + 3x - 4y} \right)}}{\mkern 1mu} {\mkern 1mu} V/m$$ is incident on a perfectly conducting slab positioned at $$x \le 0$$. The $$\overrightarrow E $$ field of the reflected wave is
24
A transmission line with a characteristic impedance of 100 $$\Omega $$ is used to match a 50 $$\Omega $$ section to a 200 $$\Omega $$ section. If the matching is to be done both at 429 MHz and 1 GHz, the tength of the transmission line can be approximately
25
The radiation pattern of an antenna in spherical co-ordinates is given by $$$F\,(\theta )\, = {\cos ^4}\,\theta \,\,\,;\,\,0\,\, \le \,\,\theta \,\, \le \,\,\pi /2$$$ The directivity of the antenna is
26
An infinitely long uniform solid wire of radius a carries a uniform dc current of density $$\widehat{\mathrm j}$$.

A hole of radius b (b < a) is now drilled along the length of the wire at a distance d from the center of the wire as shown below.

GATE ECE 2012 Electromagnetics - Maxwell Equations Question 25 English

The magnetic field inside the hole is

27
An infinitely long uniform solid wire of radius a carries a uniform dc current of density $$\widehat{\mathrm j}$$

The magnetic field at a distance r from the center of the wire is proportional to

28
In the circuit shown GATE ECE 2012 Electronic Devices and VLSI - IC Basics and MOSFET Question 59 English
29
In the three dimensional view of a silicon n-channel MOS transistor shown below, $$\delta = 20$$ nm. The transistor is of width 1 $$\mu m$$. The depletion width formed at every p-n junction is 10 nm. The relative permittivities of Si and SiO2, respectively, are 11.7 and 3.9, and $${\varepsilon _0}$$ = 8.9 $$ \times {10^{ - 12}}$$ F/m. GATE ECE 2012 Electronic Devices and VLSI - IC Basics and MOSFET Question 27 English

The gate-source overlap capacitance is approximately

30
The source of a silicon (ni = 1010 per cm3) n - channel MOS transistor has an aewa of 1 sq $$\mu m$$ and a depth of 1 $$\mu m$$ . If the dopant density in the source is 1019/cm3, the number of holes in the source region with the above volume is approximately
31
In the three dimensional view of a silicon n-channel MOS transistor shown below, $$\delta = 20$$ nm. The transistor is of width 1 $$\mu m$$. The depletion width formed at every p-n junction is 10 nm. The relative permittivities of Si and SiO2, respectively, are 11.7 and 3.9, and $${\varepsilon _0}$$ = 8.9 $$ \times {10^{ - 12}}$$ F/m. GATE ECE 2012 Electronic Devices and VLSI - IC Basics and MOSFET Question 28 English

The source-body junction capacitance is approximately

32
In the CMOS circuit shown, electron and hole mobilities are equal, and M1 and M2 are equally sized. The device M1 is in the linear region if GATE ECE 2012 Electronic Devices and VLSI - IC Basics and MOSFET Question 29 English
33
Given that $$A = \left[ {\matrix{ { - 5} & { - 3} \cr 2 & 0 \cr } } \right]$$ and $${\rm I} = \left[ {\matrix{ 1 & 0 \cr 0 & 1 \cr } } \right],$$ the value of $${A^3}$$ is
34
The direction of vector $$A$$ is radially outward
from the origin, with $$\left| A \right| = K\,{r^n}$$
where $${r^2} = {x^2} + {y^2} + {z^2}$$ and $$K$$ is constant.
The value of $$n$$ for which $$\nabla .A = 0\,\,$$ is
35
Two independent random variables $$X$$ and $$Y$$ are uniformly distributed in the interval $$\left[ { - 1,1} \right].$$ The probability that max $$\left[ {X,Y} \right]$$ is less than $$1/2$$ is
36
A fair coin is tossed till a head appears for the first time. The probability that the number of required tosses is odd, is
37
With initial condition $$x\left( 1 \right)\,\,\, = \,\,\,\,0.5,\,\,\,$$ the solution of the differential equation, $$\,\,\,t{{dx} \over {dt}} + x = t\,\,\,$$ is
38
If $$x\left[ N \right] = {\left( {1/3} \right)^{\left| n \right|}} - {\left( {1/2} \right)^n}\,u\left[ n \right],$$ then the region of convergence $$(ROC)$$ of its $$Z$$-transform in the $$Z$$-plane will be
39
The unilateral Laplace transform of $$f(t)$$ is
$$\,{1 \over {{s^2} + s + 1}}.$$ The unilateral Laplace transform of $$t$$ $$f(t)$$ is
40
Consider the differential equation
$${{{d^2}y\left( t \right)} \over {d{t^2}}} + 2{{dy\left( t \right)} \over {dt}} + y\left( t \right) = \delta \left( t \right)$$
with $$y\left( t \right)\left| {_{t = 0} = - 2} \right.$$ and $${{dy} \over {dt}}\left| {_{t = 0}} \right. = 0.$$

The numerical value of $${{dy} \over {dt}}\left| {_{t = 0}.} \right.$$ is

41
If $$x = \sqrt { - 1} ,\,\,$$ then the value of $${X^x}$$ is
42
Given $$f\left( z \right) = {1 \over {z + 1}} - {2 \over {z + 3}}.$$ If $$C$$ is a counterclockwise path in the $$z$$-plane such that
$$\left| {z + 1} \right| = 1,$$ the value of $${1 \over {2\,\pi \,j}}\oint\limits_c {f\left( z \right)dz} $$ is
43

The impedance looking into nodes 1 and 2 in the given circuit is

GATE ECE 2012 Network Theory - Network Elements Question 33 English
44

In the circuit shown below, current through the inductor is

GATE ECE 2012 Network Theory - Network Elements Question 34 English
45

If VA - VB = 6 V then VC - VD is

GATE ECE 2012 Network Theory - Network Elements Question 18 English
46
Assuming both the voltage sources are in phase the value of R for which maximum power is transferred from circuit A to circuit B is GATE ECE 2012 Network Theory - Network Theorems Question 21 English
47
With 10 V dc connected at port A in the linear nonreciprocal two-port network shown below, the following were observed:
(i) 1Ω connected at port B draws a current of 3 A
(ii) 2.5Ω connected at port B draws a current of 2 A
GATE ECE 2012 Network Theory - Network Theorems Question 19 English
With 10 V dc connected at port A, the current drawn by 7Ω connected at port B is
48
With 10 V dc connected at port A in the linear nonreciprocal two-port network shown below, the following were observed:
(i) 1Ω connected at port B draws a current of 3 A
(ii) 2.5Ω connected at port B draws a current of 2 A
GATE ECE 2012 Network Theory - Network Theorems Question 20 English
For the same network, with 6 V dc connected at port A, 1Ω connected at port B draws 7/3 A. If 8 V dc is connected to port A, the open circuit voltage at port B is
49
In the following figure, C1 and C2 are ideal capacitors. C1 has been charged to 12 V before the ideal switch S is closed at t = 0. The current i(t) for all t is. GATE ECE 2012 Network Theory - Transient Response Question 44 English
50
The average power delivered to an impedance $(4-j 3) \Omega$ by a current $5 \cos (100 \pi t+100) A$ is
51
If $$x\left[ n \right]$$= $${(1/3)^{\left| n \right|}} - {(1/2)^n}u\left[ n \right]$$, then the region of convergence (ROC) of its Z- transform in the Z-plane will be
52
The input x(t) and output y(t) of a system are related as y(t) = $$\int\limits_{ - \infty }^t x (\tau )\cos (3\tau )d\tau $$.

The system is

53
The Fourier transform of a signal h(t) is $$H(j\omega )$$ =(2 cos $$\omega $$) (sin 2$$\omega $$) / $$\omega $$. The value of h(0) is
54
Let $$y\left[ n \right]$$ denote the convolution of $$h\left[ n \right]$$ and $$g\left[ n \right]$$, where $$h\left[ n \right]$$ $$ = \,{\left( {1/2} \right)^2}\,\,u\left[ n \right]$$ and $$g\left[ n \right]\,$$ is a causal sequence. If $$y\left[ 0 \right]\,$$ $$ = \,1$$ and $$y\left[ 1 \right]\,$$ $$ = \,1/2,$$ then $$g\left[ 1 \right]$$ equals

General Aptitude

1
Choose the most appropriate alternative from the options given below to complete the following sentence:

If the tired soldier wanted to lie down, he _______ the mattress out on the balcony.

2
Choose the most appropriate word from the options given below to complete the following sentence:

Given the seriousness of the situation that he had to face, his ________ was impressive.

3
Which one of the following options is the closest in meaning to the word given below?

Latitude

4
One of the parts (A, B, C, D) in the sentence given below contains an ERROR. Which one of the following is INCORRECT?

I requested that he should be given the driving test today instead of tomorrow.

5
If (1.001)1259 = 3.52 and (1.001)2062 = 7.85, then (1.001)3321 =
6
Raju has 14 currency notes in his pocket consisting of only Rs. 20 notes and Rs. 10 notes. The total money value of the notes is Rs. 230. The number of Rs. 10 notes that Raju has is
7
The data given in the following table summarizes the monthly budget of an average household. GATE ECE 2012 General Aptitude - Numerical Ability Question 57 English

The approximate percentage of the monthly budget NOT spent on savings is

8
A and B are friends. They decide to meet between 1 PM and 2 PM on a given day. There is a condition that whoever arrives first will not wait for the other for more than 15 minutes. The probability that they will meet on that day is
9
There are eight bags of rice looking alike, seven of which have equal weight and one is slightly heavier. The weighing balance is of unlimited capacity. Using this balance, the minimum number of weighings required to identify the heavier bag is
10

One of the legacies of the Roman legions was discipline. In the legions, military law prevailed and discipline was brutal. Discipline on the battlefield kept units obedient, intact and fighting, even when the odds and conditions were against them.

Which one of the following statements best sums up the meaning of the above passage?
EXAM MAP
Medical
NEETAIIMS
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
Staff Selection Commission
SSC CGL Tier I
CBSE
Class 12