GATE 2020 EC – Previous Year Questions with Solutions
All 65 questions of GATE 2020 EC with answers and explanations. Read each question, then practise it by topic or as a full paper.
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- Question 1 – The untimely loss of life is a cause of serious global concern as thousands of people get killed accidents every year while many other die diseases…
- Question 2 – He was not only accused of theft of conspiracy.
- Question 3 – Select the word that fits the analogy: Explicit : Implicit :: Express :
- Question 4 – The Canadian constitution requires that equal importance be given to English and French. Last year, Air Canada lost a lawsuit, and had to pay a…
- Question 5 – A superadditive function f() satisfies the following property f(x 1+x 2) f(x 1)+f(x 2) Which of the following functions is a superadditive function…
- Question 6 – The global financial crisis in 2008 is considered to be the most serious world-wide financial crisis, which started with the sub-prime lending crisis…
- Question 7 – It is quarter past three in your watch. The angle between the hour hand and the minute hand is .
- Question 8 – A circle with centre O is shown in the figure. A rectangle PQRS of maximum possible area is inscribed in the circle. If the radius of the circle is a,…
- Question 9 – a,b,c are real numbers. The quadratic equation ax2-bx+c=0 has equal roots, which is , then
- Question 10 – The following figure shows the data of students enrolled in 5 years (2014 to 2018) for two schools P and Q. During this period, the ratio of the…
- Question 11 – If v 1, v 2,, v 6 are six vectors in R4, which one of the following statements is FALSE?
- Question 12 – For a vector field A, which one of the following is FALSE?
- Question 13 – The partial derivative of the function f(x,y,z)=e1-x y+xze-1/(1+y2) with respect to x at the point (1,0,e) is
- Question 14 – The general solution of d2ydx2-6dydx+9y=0 is
- Question 15 – The output y[n] of a discrete-time system for an input x[n] is y[n]= - k n x[k] . The unit impulse response of the system is
- Question 16 – A single crystal intrinsic semiconductor is at a temperature of 300 K with effective density of states for holes twice that of electrons. The thermal…
- Question 17 – Consider the recombination process via bulk traps in a forward biased pn homojunction diode. The maximum recombination rate is U max. If the electron…
- Question 18 – The components in the circuit shown below are ideal. If the op-amp is in positive feedback and the input voltage V i is a sine wave of amplitude 1 V,…
- Question 19 – In the circuit shown below, the Thevenin voltage V TH is
- Question 20 – The figure below shows a multiplexer where S 1 and S 0 are the select lines, I 0 to I 3 are the input data lines, EN is the enable line, and F(P,Q,R)…
- Question 21 – The pole-zero map of a rational function G(s) is shown below. When the closed contour is mapped into the G(s)-plane, then the mapping encircles
- Question 22 – A digital communication system transmits a block of N bits. The probability of error in decoding a bit is . The error event of each bit is independent…
- Question 23 – The impedances Z=jX, for all X in the range (-,), map to the Smith chart as
- Question 24 – Which one of the following pole-zero plots corresponds to the transfer function of an LTI system characterized by the input-output difference equation…
- Question 25 – In the given circuit, the two-port network has the impedance matrix [Z]=bmatrix40&60\\60&120bmatrix. The value of Z L for which maximum power is…
- Question 26 – The current in the RL-circuit shown below is i(t)=10(5t-/4) A. The value of the inductor (rounded off to two decimal places) is H.
- Question 27 – In the circuit shown below, all the components are ideal and the input voltage is sinusoidal. The magnitude of the steady-state output V o (rounded…
- Question 28 – In the circuit shown below, all the components are ideal. If V i is +2 V, the current I o sourced by the op-amp is mA.
- Question 29 – In an 8085 microprocessor, the number of address lines required to access a 16 K byte memory bank is .
- Question 30 – A 10-bit D/A converter is calibrated over the full range from 0 to 10 V. If the input to the D/A converter is 13A (in hex), the output (rounded off to…
- Question 31 – A transmission line of length 3/4 and having a characteristic impedance of 50\ is terminated with a load of 400\ . The impedance (rounded off to two…
- Question 32 – A binary random variable X takes the value +2 or -2. The probability P(X=+2)=. The value of (rounded off to one decimal place), for which the entropy…
- Question 33 – The loop transfer function of a negative feedback system is G(s)H(s)=K(s+11)s(s+2)(s+8). The value of K, for which the system is marginally stable, is…
- Question 34 – The random variable Y= -W(t)(t)\,dt,where (t)=cases1;&5 t7\\0;&otherwisecases and W(t) is a real white Gaussian noise process with two-sided power…
- Question 35 – The two sides of a fair coin are labelled as 0 and 1. The coin is tossed two times independently. Let M and N denote the labels of the outcomes of…
- Question 36 – Consider the following system of linear equations. x 1+2x 2=b 1;2x 1+4x 2=b 2;3x 1+7x 2=b 3;3x 1+9x 2=b 4 Which one of the following conditions…
- Question 37 – Which one of the following options contains two solutions of the differential equation dydx=(y-1)x?
- Question 38 – The current I in the given network is
- Question 39 – A finite duration discrete-time signal x[n] is obtained by sampling the continuous-time signal x(t)=(200 t) at sampling instants t=n/400, n=0,1,,7.…
- Question 40 – For the given circuit, which one of the following is the correct state equation?
- Question 41 – A one-sided abrupt pn junction diode has a depletion capacitance C D of 50 pF at a reverse bias of 0.2 V. The plot of 1/C D2 versus the applied…
- Question 42 – The band diagram of a p-type semiconductor with a band-gap of 1 eV is shown. Using this semiconductor, a MOS capacitor having V TH of -0.16 V, C' ox…
- Question 43 – The base of an npn BJT T1 has a linear doping profile N B(x) as shown below. The base of another npn BJT T2 has a uniform doping N B of 1017\ cm-3.…
- Question 44 – A pn junction solar cell of area 1.0 cm2, illuminated uniformly with 100 mW cm-2, has the following parameters: Efficiency =15\%, open circuit voltage…
- Question 45 – For the BJT in the amplifier shown below, V BE=0.7 V, kT/q=26 mV. Assume that BJT output resistance (r o) is very high and the base current is…
- Question 46 – An enhancement MOSFET of threshold voltage 3 V is being used in the sample and hold circuit given below. Assume that the substrate of the MOS device…
- Question 47 – Using the incremental low frequency small-signal model of the MOS device, the Norton equivalent resistance of the following circuit is
- Question 48 – P, Q, and R are the decimal integers corresponding to the 4-bit binary number 1100 considered in signed magnitude, 1's complement, and 2's complement…
- Question 49 – The state diagram of a sequence detector is shown below. State S 0 is the initial state of the sequence detector. If the output is 1, then
- Question 50 – The characteristic equation of a system is s3+3s2+(K+2)s+3K=0. In the root locus plot for the given system, as K varies from 0 to , the break-away or…
- Question 51 – The components in the circuit given below are ideal. If R=2\ k and C=1\ F, the -3 dB cut-off frequency of the circuit in Hz is
- Question 52 – For the modulated signal x(t)=m(t)(2 f ct), the message signal m(t)=4(1000 t) and the carrier frequency f c is 1 MHz. The signal x(t) is passed…
- Question 53 – For an infinitesimally small dipole in free space, the electric field E in the far field is proportional to (e-jkr/r), where k=2/. A vertical…
- Question 54 – In the voltage regulator shown below, V I is the unregulated input at 15 V. Assume V BE=0.7 V and the base current is negligible for both the BJTs. If…
- Question 55 – The magnetic field of a uniform plane wave in vacuum is given by H(x,y,z,t)=( a x+2 a y+b\, a z)( t+3x-y-z). The value of b is .
- Question 56 – For a 2-port network consisting of an ideal lossless transformer, the parameter S 21 (rounded off to two decimal places) for a reference impedance of…
- Question 57 – S PM(t) and S FM(t) as defined below, are the phase modulated and the frequency modulated waveforms, respectively, corresponding to the message signal…
- Question 58 – In a digital communication system, a symbol S randomly chosen from the set \s 1,s 2,s 3,s 4\ is transmitted. It is given that s 1=-3, s 2=-1, s 3=+1…
- Question 59 – A system with transfer function G(s)=1(s+1)(s+a), a>0 is subjected to an input 53t. The steady state output of the system is 110(3t-1.892). The value…
- Question 60 – For the components in the sequential circuit shown below, t pd is the propagation delay, t setup is the setup time, and t hold is the hold time. The…
- Question 61 – For the solid S shown below, the value of Sx\,dx\,dy\,dz (rounded off to two decimal places) is .
- Question 62 – X() is the Fourier transform of x(t) shown below. The value of - X() 2\,d (rounded off to two decimal places) is .
- Question 63 – The transfer function of a stable discrete-time LTI system is H(z)=K(z-)z+0.5, where K and are real numbers. The value of (rounded off to one decimal…
- Question 64 – X is a random variable with uniform probability density function in the interval [-2,10]. For Y=2X-6, the conditional probability P(Y7\, \,X5)…
- Question 65 – Consider the following closed loop control system where G(s)=1s(s+1) and C(s)=Ks+1s+3. If the steady state error for a unit ramp input is 0.1, then…