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General Aptitude

10 Questions
GATE→2025→General Aptitude→Verbal Ability
Q1
MCQ[1 Mark]
Here are two analogous groups, Group-I and Group-II, that list words in their decreasing order of intensity. Identify the missing word in Group-II. Group-I: Abuse → Insult → Ridicule Group-II: [Missing] → Praise → Appreciate
GATE→2025→General Aptitude→Verbal Ability
Q2
MCQ[1 Mark]
Had I learnt acting as a child, I ______ a famous film star. Select the most appropriate option to complete the above sentence.
GATE→2025→General Aptitude→Quantitative Aptitude
Q3
MCQ[1 Mark]
The 12 musical notes are given as C, C#C^{\#}, D, D#D^{\#}, E, F, F#F^{\#}, G, G#G^{\#}, A, A#A^{\#} and B. Frequency of each note is 212\sqrt[12]{2} times the frequency of the previous note. If the frequency of the note C is 130.8 Hz, then the ratio of frequencies of notes F#F^{\#} and C is:
GATE→2025→General Aptitude→Quantitative Aptitude
Q4
MCQ[1 Mark]
The following figures show three curves generated using an iterative algorithm. The total length of the curve generated after 'Iteration n' is: Note: The figures shown are representative.
Figure for Question 4
GATE→2025→General Aptitude→Quantitative Aptitude
Q5
MCQ[1 Mark]
Which one of the following plots represents f(x)=−∣x∣xf(x) = -\frac{|x|}{x}, where x is a non-zero real number? Note: The figures shown are representative.
Figure for Question 5
GATE→2025→General Aptitude→Verbal Ability
Q6
MCQ[2 Marks]
Identify the option that has the most appropriate sequence such that a coherent paragraph is formed: P. Over time, such adaptations lead to significant evolutionary changes with the potential to shape the development of new species. Q. In natural world, organisms constantly adapt to their environments in response to challenges and opportunities. R. This process of adaptation is driven by the principle of natural selection, where favorable traits increase an organism's chances of survival and reproduction. S. As environments change, organisms that can adapt their behavior, structure and physiology to such changes are more likely to survive.
GATE→2025→General Aptitude→Quantitative Aptitude
Q7
MCQ[2 Marks]
A stick of length one meter is broken at two locations at distances of b1b_{1} and b2b_{2} from the origin (0), as shown in the figure. Note that 0<b1<b2<10 < b_{1} < b_{2} < 1. Which one of the following is NOT a necessary condition for forming a triangle using the three pieces? Note: All lengths are in meter. The figure shown is representative.
Figure for Question 7
GATE→2025→General Aptitude→Quantitative Aptitude
Q8
MCQ[2 Marks]
Eight students (P, Q, R, S, T, U, V, and W) are playing musical chairs. The figure indicates their order of position at the start of the game. They play the game by moving forward in a circle in the clockwise direction. After the 1st1^{st} round, 4th4^{th} student behind P leaves the game. After 2nd2^{nd} round, 5th5^{th} student behind Q leaves the game. After 3rd3^{rd} round, 3rd3^{rd} student behind V leaves the game. After 4th4^{th} round, 4th4^{th} student behind U leaves the game. Who all are left in the game after the 4th4^{th} round? Note: The figure shown is representative.
Figure for Question 8
GATE→2025→General Aptitude→Data Interpretation
Q9
MCQ[2 Marks]
The table lists the top 5 nations according to the number of gold medals won in a tournament; also included are the number of silver and the bronze medals won by them. Based only on the data provided in the table, which one of the following statements is INCORRECT? Nation | Gold | Silver | Bronze USA | 40 | 44 | 41 Canada | 39 | 24 | 27 Japan | 12 | 20 | 13 Australia | 19 | 17 | 16 France | 16 | 26 | 22
GATE→2025→General Aptitude→Quantitative Aptitude
Q10
MCQ[2 Marks]
An organization allows its employees to work independently on consultancy projects but charges an overhead on the consulting fee. The overhead is 20% of the consulting fee, if the fee is up to 5,00,000. For higher fees, the overhead is 1,00,000 plus 10% of the amount by which the fee exceeds 5,00,000. The government charges a Goods and Services Tax of 18% on the total amount (the consulting fee plus the overhead). An employee of the organization charges this entire amount, i.e., the consulting fee, overhead, and tax, to the client. If the client cannot pay more than ₹10,00,000, what is the maximum consulting fee that the employee can charge?

Engineering Mathematics

11 Questions
GATE→2025→Engineering Mathematics→Linear Algebra
Q11
MCQ[1 Mark]
Consider the matrix A below: A=[2345067800αβ000γ]A = \begin{bmatrix} 2 & 3 & 4 & 5 \\ 0 & 6 & 7 & 8 \\ 0 & 0 & \alpha & \beta \\ 0 & 0 & 0 & \gamma \end{bmatrix} For which of the following combinations of α\alpha, β\beta, and γ\gamma, is the rank of A at least three?
GATE→2025→Engineering Mathematics→Complex Analysis
Q12
MCQ[1 Mark]
Consider the following series: (i) ∑n=1∞1n\sum_{n=1}^{\infty} \frac{1}{\sqrt{n}} (ii) ∑n=1∞1n(n+1)\sum_{n=1}^{\infty} \frac{1}{n(n+1)} (iii) ∑n=1∞1n!\sum_{n=1}^{\infty} \frac{1}{n!} Choose the correct option.
GATE→2025→Engineering Mathematics→Probability and Statistics
Q13
MCQ[1 Mark]
A pot contains two red balls and two blue balls. Two balls are drawn from this pot randomly without replacement. What is the probability that the two balls drawn have different colours?
GATE→2025→Engineering Mathematics→Calculus
Q14
MSQ[1 Mark]
Consider the function f:R→Rf:\mathbb{R} \to \mathbb{R} defined as f(x)=2x3−3x2−12x+1f(x) = 2x^3 - 3x^2 - 12x + 1. Which of the following statements is/are correct? (Here, R\mathbb{R} is the set of real numbers.)
GATE→2025→Engineering Mathematics→Differential Equations
Q15
NAT[1 Mark]
The function y(t)y(t) satisfies t2y′′(t)−2ty′(t)+2y(t)=0t^2 y''(t) - 2ty'(t) + 2y(t) = 0, where y′(t)y'(t) and y′′(t)y''(t) denote the first and second derivatives of y(t)y(t), respectively. Given y′(0)=1y'(0) = 1 and y′(1)=−1y'(1) = -1, the maximum value of y(t)y(t) over [0,1] is ______ (rounded off to two decimal places).
GATE→2025→Engineering Mathematics→Calculus
Q16
MSQ[2 Marks]
Consider a non-negative function f(x)f(x) which is continuous and bounded over the interval [2, 8]. Let M and m denote, respectively, the maximum and the minimum values of f(x)f(x) over the interval. Among the combinations of α\alpha and β\beta given below, choose the one(s) for which the inequality β≤∫28f(x)dx≤α\beta \le \int_2^8 f(x) dx \le \alpha is guaranteed to hold.
GATE→2025→Engineering Mathematics→Complex Analysis
Q17
MSQ[2 Marks]
Which of the following statements involving contour integrals (evaluated counter-clockwise) on the unit circle C in the complex plane is/are TRUE?
GATE→2025→Engineering Mathematics→Probability and Statistics
Q18
MSQ[2 Marks]
The random variable X takes values in {−1,0,1}\{-1, 0, 1\} with probabilities P(X=−1)=P(X=1)=αP(X=-1) = P(X=1) = \alpha and P(X=0)=1−2αP(X=0) = 1-2\alpha, where 0<α<120 < \alpha < \frac{1}{2}: Let g(α)g(\alpha) denote the entropy function of X (in bits), parameterized by α\alpha. Which of the following statements is/are TRUE?
GATE→2025→Engineering Mathematics→Probability and Statistics
Q19
NAT[2 Marks]
Two fair dice (with faces labeled 1, 2, 3, 4, 5, and 6) are rolled. Let the random variable X denote the sum of the outcomes obtained. The expectation of X is ______ (rounded off to two decimal places).
GATE→2025→Engineering Mathematics→Linear Algebra
Q20
NAT[2 Marks]
Consider the vectors a=[11]a = \begin{bmatrix} 1 \\ 1 \end{bmatrix}, b=[032]b = \begin{bmatrix} 0 \\ 3\sqrt{2} \end{bmatrix}. For real-valued scalar variable X, the value of min⁡x∥ax−b∥2\min_x \|ax - b\|_2 is ______ (rounded off to two decimal places). (∥⋅∥2\|\cdot\|_2 denotes the Euclidean norm)
GATE→2025→Engineering Mathematics→Probability and Statistics
Q21
NAT[2 Marks]
X and Y are Bernoulli random variables taking values in {0,1}\{0,1\}. The joint probability mass function of the random variables is given by: P(X=0,Y=0)=0.06P(X=0, Y=0) = 0.06, P(X=0,Y=1)=0.14P(X=0, Y=1) = 0.14, P(X=1,Y=0)=0.24P(X=1, Y=0) = 0.24, P(X=1,Y=1)=0.56P(X=1, Y=1) = 0.56. The mutual information I(X;Y)I(X;Y) is ______ (rounded off to two decimal places).

Networks, Signals and Systems

9 Questions
GATE→2025→Networks, Signals and Systems→LTI Systems
Q22
MCQ[1 Mark]
Consider the discrete-time system below with input x[n]x[n] and output y[n]y[n]. In the figure, h1[n]h_1[n] and h2[n]h_2[n] denote the impulse responses of LTI Subsystems 1 and 2, respectively. Also, δ[n]\delta[n] is the unit impulse, and b>0b > 0. Assuming h2[n]≠δ[n]h_2[n] \neq \delta[n] the overall system (denoted by the dashed box) is
Figure for Question 22
GATE→2025→Networks, Signals and Systems→Continuous-time Signals
Q23
MCQ[1 Mark]
Consider a continuous-time, real-valued signal f(t)f(t) whose Fourier transform F(ω)=∫−∞∞f(t)exp⁡(−jωt)dtF(\omega) = \int_{-\infty}^{\infty} f(t) \exp(-j \omega t) dt exists. Which one of the following statements is always TRUE?
GATE→2025→Networks, Signals and Systems→Circuit Analysis
Q24
MCQ[1 Mark]
Consider a part of an electrical network as shown below. Some node voltages, and the current flowing through the 3Ω3\Omega resistor are as indicated. The voltage (in Volts) at node X is ______
Figure for Question 24
GATE→2025→Networks, Signals and Systems→Circuit Analysis
Q25
MCQ[1 Mark]
Let ici_c, iLi_L and iRi_R be the currents flowing through the capacitor, inductor, and resistor, respectively, in the circuit given below. The AC admittances are given in Siemens (S). Which one of the following is TRUE?
Figure for Question 25
GATE→2025→Networks, Signals and Systems→Discrete-time Signals
Q26
MSQ[1 Mark]
Let x[n]x[n] be a discrete-time signal whose Z-transform is X(z)X(z). Which of the following statements is/are TRUE?
GATE→2025→Networks, Signals and Systems→Continuous-time Signals
Q27
MCQ[2 Marks]
Consider a continuous-time finite-energy signal f(t)f(t) whose Fourier transform vanishes outside the frequency interval [−ωc,ωc][-\omega_c, \omega_c], where ωc\omega_c is in rad/sec. The signal f(t)f(t) is uniformly sampled to obtain y(t)=f(t)p(t)y(t) = f(t)p(t). Here, p(t)=∑n=−∞∞δ(t−τ−nTs)p(t) = \sum_{n=-\infty}^{\infty} \delta(t - \tau - nT_s), with δ(t)\delta(t) being the Dirac impulse, Ts>0T_s > 0, and τ>0\tau > 0. The sampled signal y(t)y(t) is passed through an ideal lowpass filter h(t)=ωcTssin⁡(ωct)πωcth(t) = \omega_c T_s \frac{\sin(\omega_c t)}{\pi \omega_c t} with cutoff frequency ωc\omega_c and passband gain TsT_s. The output of the filter is given by
GATE→2025→Networks, Signals and Systems→Circuit Analysis
Q28
MCQ[2 Marks]
In the circuit below, M1M_1 is an ideal AC voltmeter and M2M_2 is an ideal AC ammeter. The source voltage (in Volts) is vs(t)=100cos⁡(200t)v_s(t) = 100 \cos(200 t). What should be the value of the variable capacitor C such that the RMS readings on M1M_1 and M2M_2 are 25 V and 5 A, respectively?
Figure for Question 28
GATE→2025→Networks, Signals and Systems→Time and Frequency Domain Analysis of Linear Circuits
Q29
MCQ[2 Marks]
The Z-parameter matrix of a two port network relates the port voltages and port currents as follows: [V1V2]=Z[I1I2]\begin{bmatrix} V_1 \\ V_2 \end{bmatrix} = Z \begin{bmatrix} I_1 \\ I_2 \end{bmatrix} The Z-parameter matrix (with each entry in Ohms) of the network shown below is:
Figure for Question 29
GATE→2025→Networks, Signals and Systems→Continuous-time Signals
Q30
MSQ[2 Marks]
Let f(t)f(t) be a periodic signal with fundamental period T0>0T_0 > 0. Consider the signal y(t)=f(αt)y(t) = f(\alpha t), where α>1\alpha > 1. The Fourier series expansions of f(t)f(t) and y(t)y(t) are given by f(t)=∑k=−∞∞ckej2πT0ktf(t) = \sum_{k=-\infty}^{\infty} c_k e^{j \frac{2\pi}{T_0} k t} and y(t)=∑k=−∞∞dkej2παT0kty(t) = \sum_{k=-\infty}^{\infty} d_k e^{j \frac{2\pi \alpha}{T_0} k t}. Which of the following statements is/are TRUE?

Electronic Devices

4 Questions
GATE→2025→Electronic Devices→Semiconductor Physics and Carrier Transport
Q31
MSQ[1 Mark]
Which of the following can be used as an n-type dopant for silicon? Select the correct option(s).
GATE→2025→Electronic Devices→Semiconductor Physics and Carrier Transport
Q32
MCQ[2 Marks]
The intrinsic carrier concentration of a semiconductor is 2.5×1016/m32.5 \times 10^{16} / m^3 at 300 K. If the electron and hole mobilities are 0.15 m2/Vs0.15~m^2/Vs and 0.05 m2/Vs0.05~m^2/Vs, respectively, then the intrinsic resistivity of the semiconductor (in kΩ⋅mk\Omega \cdot m) at 300 K is (Charge of an electron e=1.6×10−19Ce = 1.6 \times 10^{-19} C.)
GATE→2025→Electronic Devices→Semiconductor Physics and Carrier Transport
Q33
MCQ[2 Marks]
The electron mobility μn\mu_n in a non-degenerate germanium semiconductor at 300 K is 0.38 m2/Vs0.38~m^2/Vs. The electron diffusivity DnD_n at 300 K (in cm2/scm^2/s, rounded off to the nearest integer) is (Consider the Boltzmann constant kB=1.38×10−23J/Kk_B = 1.38 \times 10^{-23} J/K and the charge of an electron e=1.6×10−19Ce = 1.6 \times 10^{-19} C.)
GATE→2025→Electronic Devices→Diodes, BJTs, MOS Capacitors, MOSFETs, and Optoelectronic Devices
Q34
NAT[2 Marks]
An ideal p-n junction germanium diode has a reverse saturation current of 10 μA10~\mu A at 300 K. The voltage (in Volts, rounded off to two decimal places) to be applied across the junction to get a forward bias current of 100 mA at 300 K is ______ (Consider the Boltzmann constant kB=1.38×10−23J/Kk_B = 1.38 \times 10^{-23} J/K and the charge of an electron e=1.6×10−19Ce = 1.6 \times 10^{-19} C.)

Analog Circuits

10 Questions
GATE→2025→Analog Circuits→BJT and MOSFET Amplifiers
Q35
MCQ[1 Mark]
A simplified small-signal equivalent circuit of a BJT-based amplifier is given below. The small-signal voltage gain vo/vSv_o / v_S (in V/V) is
Figure for Question 35
GATE→2025→Analog Circuits→BJT and MOSFET Amplifiers
Q36
MCQ[1 Mark]
The ideal BJT in the circuit given below is biased in the active region with a β\beta of 100. If IBI_B is 10 μA10~\mu A, then VCEV_{CE} (in Volts, rounded off to two decimal places) is
Figure for Question 36
GATE→2025→Analog Circuits→Op-amp Circuits and Compensation
Q37
MSQ[1 Mark]
Which of the following statements is/are TRUE with respect to an ideal opamp?
GATE→2025→Analog Circuits→BJT and MOSFET Amplifiers
Q38
MSQ[1 Mark]
Which of the following statements is/are TRUE with respect to ideal MOSFET-based DC-coupled single-stage amplifiers having finite load resistors?
GATE→2025→Analog Circuits→Op-amp Circuits and Compensation
Q39
NAT[1 Mark]
All the components in the bandpass filter given below are ideal. The lower -3 dB frequency of the filter is 1 MHz. The upper -3 dB frequency (in MHz, rounded off to the nearest integer) is ______
Figure for Question 39
GATE→2025→Analog Circuits→Op-amp Circuits and Compensation
Q40
NAT[1 Mark]
A 4-bit weighted-resistor DAC with inputs b3b_3, b2b_2, b1b_1, and b0b_0 (MSB to LSB) is designed using an ideal opamp, as shown below. The switches are closed when the corresponding input bits are logic '1' and open otherwise. When the input b3b2b1b0b_3 b_2 b_1 b_0 changes from 1110 to 1101, the magnitude of the change in the output voltage VOV_O (in mV, rounded off to the nearest integer) is ______
Figure for Question 40
GATE→2025→Analog Circuits→BJT and MOSFET Amplifiers
Q41
MCQ[2 Marks]
The identical MOSFETS M1M_1 and M2M_2 in the circuit given below are ideal and biased in the saturation region. M1M_1 and M2M_2 have a transconductance gmg_m of 5 mS. The input signals (in Volts) are: V1=2.5+0.01sin⁡ωtV_1 = 2.5 + 0.01 \sin \omega t, V2=2.5−0.01sin⁡ωtV_2 = 2.5 - 0.01 \sin \omega t. The output signal V3V_3 (in Volts) is
Figure for Question 41
GATE→2025→Analog Circuits→BJT and MOSFET Amplifiers
Q42
MCQ[2 Marks]
In the circuit shown, the identical transistors Q1 and Q2 are biased in the active region with β=120\beta = 120. The Zener diode is in the breakdown region with VZ=5V_Z = 5 V and IZ=25I_Z = 25 mA. If IL=12I_L = 12 mA and VEB1=VEB2=0.7V_{EB1} = V_{EB2} = 0.7 V then the values of R1R_1 and R2R_2 (in kΩk\Omega, rounded off to one decimal place) are respectively.
Figure for Question 42
GATE→2025→Analog Circuits→Diode Circuits
Q43
MSQ[2 Marks]
All the diodes in the circuit given below are ideal. Which of the following plots is/are correct when VIV_I (in Volts) is swept from -M to M?
Figure for Question 43
GATE→2025→Analog Circuits→Diode Circuits
Q44
NAT[2 Marks]
The diode in the circuit shown below is ideal. The input voltage (in Volts) is given by VI=10sin⁡(100πt)V_I = 10 \sin(100\pi t), where time t is in seconds. The time duration (in ms, rounded off to two decimal places) for which the diode is forward biased during one period of the input is ______
Figure for Question 44

Digital Circuits

5 Questions
GATE→2025→Digital Circuits→Number Representations and Combinatorial Circuits
Q45
MCQ[1 Mark]
A 3-input majority logic gate has inputs X, Y, and Z. The output F of the gate is logic '1' if two or more of the inputs are logic '1'. The output F is logic '0' if two or more of the inputs are logic '0'. Which one of the following options is a Boolean expression of the output F?
GATE→2025→Digital Circuits→Number Representations and Combinatorial Circuits
Q46
MCQ[1 Mark]
A full adder and an XOR gate are used to design a digital circuit with inputs X, Y, and Z, and output F, as shown below. The input Z is connected to the carry-in input of the full adder. If the input Z is set to logic '1', then the circuit functions as ______ with X and Y as inputs.
Figure for Question 46
GATE→2025→Digital Circuits→Sequential Circuits, Data Converters, and Memories
Q47
MCQ[2 Marks]
A 10-bit analog-to-digital converter (ADC) has a sampling frequency of 1 MHz and a full scale voltage of 3.3 V. For an input sinusoidal signal with frequency 500 kHz, the maximum SNR (in dB, rounded off to two decimal places) and the data rate (in Mbps) at the output of the ADC are respectively.
GATE→2025→Digital Circuits→Sequential Circuits, Data Converters, and Memories
Q48
MCQ[2 Marks]
A positive-edge-triggered sequential circuit is shown below. There are no timing violations in the circuit. Input P0 is set to logic '0' and P1 is set to logic '1' at all times. The timing diagram of the inputs SEL and S are also shown below. The sequence of output Y from time T0T_0 to T3T_3 is
Figure for Question 48
GATE→2025→Digital Circuits→Sequential Circuits, Data Converters, and Memories
Q49
NAT[2 Marks]
In the circuit shown below, the AND gate has a propagation delay of 1 ns. The edge-triggered flip-flops have a set-up time of 2 ns, a hold-time of 0 ns, and a clock-to-Q delay of 2 ns. The maximum clock frequency (in MHz, rounded off to the nearest integer) such that there are no setup violations is ______
Figure for Question 49

Control Systems

6 Questions
GATE→2025→Control Systems→Control System Components, Transfer Functions, and Stability Analysis
Q50
MCQ[1 Mark]
The Nyquist plot of a system is given in the figure below. Let ωP\omega_P, ωQ\omega_Q, ωR\omega_R, and ωS\omega_S be the positive frequencies at the points P, Q, R, and S, respectively. Which one of the following statements is TRUE?
Figure for Question 50
GATE→2025→Control Systems→Control System Components, Transfer Functions, and Stability Analysis
Q51
MSQ[1 Mark]
Consider the unity-negative-feedback system shown in Figure (i) below, where gain K≥0K \ge 0. The root locus of this system is shown in Figure (ii) below. For what value(s) of K will the system in Figure (i) have a pole at −1+j1-1+j1?
Figure for Question 51
GATE→2025→Control Systems→Frequency Response, Compensators, Controllers, and State Variable Models
Q52
MCQ[2 Marks]
Let G(s)=110s2G(s) = \frac{1}{10s^2} be the transfer function of a second-order system. A controller M(s)M(s) is connected to the system G(s)G(s) in the configuration shown below. Consider the following statements. (i) There exists no controller of the form M(s)=KIsM(s) = \frac{K_I}{s}, where KIK_I is a positive real number, such that the closed loop system is stable. (ii) There exists at least one controller of the form M(s)=KP+sKDM(s) = K_P + s K_D, where KPK_P and KDK_D are positive real numbers, such that the closed loop system is stable. Which one of the following options is correct?
Figure for Question 52
GATE→2025→Control Systems→Control System Components, Transfer Functions, and Stability Analysis
Q53
MCQ[2 Marks]
Consider the polynomial p(s)=s5+7s4+3s3−33s2+2s−40p(s) = s^5 + 7s^4 + 3s^3 - 33s^2 + 2s - 40. Let (L,I,R)(L, I, R) be defined as follows: L is the number of roots of p(s)p(s) with negative real parts. I is the number of roots of p(s)p(s) that are purely imaginary. R is the number of roots of p(s)p(s) with positive real parts. Which one of the following options is correct?
GATE→2025→Control Systems→Frequency Response, Compensators, Controllers, and State Variable Models
Q54
MSQ[2 Marks]
Consider a system where x1(t)x_1(t), x2(t)x_2(t), and x3(t)x_3(t) are three internal state signals and u(t)u(t) is the input signal. The differential equations governing the system are given by ddt[x1(t)x2(t)x3(t)]=[2000−20000][x1(t)x2(t)x3(t)]+[111]u(t)\frac{d}{dt} \begin{bmatrix} x_1(t) \\ x_2(t) \\ x_3(t) \end{bmatrix} = \begin{bmatrix} 2 & 0 & 0 \\ 0 & -2 & 0 \\ 0 & 0 & 0 \end{bmatrix} \begin{bmatrix} x_1(t) \\ x_2(t) \\ x_3(t) \end{bmatrix} + \begin{bmatrix} 1 \\ 1 \\ 1 \end{bmatrix} u(t). Which of the following statements is/are TRUE?
GATE→2025→Control Systems→Control System Components, Transfer Functions, and Stability Analysis
Q55
MSQ[2 Marks]
Consider a system represented by the block diagram shown below. Which of the following signal flow graphs represent(s) this system? Choose the correct option(s).
Figure for Question 55

Communications

6 Questions
GATE→2025→Communications→Random Processes and Analog Communications
Q56
MCQ[1 Mark]
Consider a frequency-modulated (FM) signal f(t)=Accos⁡(2πfct+3sin⁡(2πf1t)+4sin⁡(6πf1t))f(t) = A_c \cos(2\pi f_c t + 3\sin(2\pi f_1 t) + 4\sin(6\pi f_1 t)), where AcA_c and fcf_c are, respectively, the amplitude and frequency (in Hz) of the carrier waveform. The frequency f1f_1 is in Hz, and assume that fc>100f1f_c > 100 f_1. The peak frequency deviation of the FM signal in Hz is
GATE→2025→Communications→Information Theory and Digital Communications
Q57
MCQ[1 Mark]
Consider an additive white Gaussian noise (AWGN) channel with bandwidth W and noise power spectral density N02\frac{N_0}{2}. Let PavP_{av} denote the average transmit power constraint. Which one of the following plots illustrates the dependence of the channel capacity C on the bandwidth W (keeping PavP_{av} and N0N_0 fixed)?
Figure for Question 57
GATE→2025→Communications→Random Processes and Analog Communications
Q58
MSQ[1 Mark]
Consider a message signal m(t)m(t) which is bandlimited to [−W,W][-W, W], where W is in Hz. Consider the following two modulation schemes for the message signal: Double sideband-suppressed carrier (DSB-SC): fDSB(t)=Acm(t)cos⁡(2πfct)f_{DSB}(t) = A_c m(t) \cos(2\pi f_c t) Amplitude modulation (AM): fAM(t)=Ac(1+μm(t))cos⁡(2πfct)f_{AM}(t) = A_c (1 + \mu m(t)) \cos(2\pi f_c t) Here, AcA_c and fcf_c are the amplitude and frequency (in Hz) of the carrier, respectively. In the case of AM, μ\mu denotes the modulation index. Consider the following statements: (i) An envelope detector can be used for demodulation in the DSB-SC scheme if m(t)>0m(t) > 0 for all t. (ii) An envelope detector can be used for demodulation in the AM scheme only if m(t)>0m(t) > 0 for all t.
GATE→2025→Communications→Information Theory and Digital Communications
Q59
NAT[1 Mark]
The generator matrix of a (6,3)(6,3) binary linear block code is given by G=[100101010011001110]G = \begin{bmatrix} 1 & 0 & 0 & 1 & 0 & 1 \\ 0 & 1 & 0 & 0 & 1 & 1 \\ 0 & 0 & 1 & 1 & 1 & 0 \end{bmatrix}. The minimum Hamming distance dmind_{min} between codewords equals ______ (answer in integer).
GATE→2025→Communications→Information Theory and Digital Communications
Q60
MCQ[2 Marks]
A source transmits symbol S that takes values uniformly at random from the set {−2,0,2}\{-2, 0, 2\}. The receiver obtains Y=S+NY = S + N where N is a zero-mean Gaussian random variable independent of S. The receiver uses the maximum likelihood decoder to estimate the transmitted symbol S. Suppose the probability of symbol estimation error PeP_e is expressed as follows: Pe=αP(N>1)P_e = \alpha P(N > 1), where P(N>1)P(N > 1) denotes the probability that N exceeds 1. What is the value of α\alpha?
GATE→2025→Communications→Random Processes and Analog Communications
Q61
MCQ[2 Marks]
Consider a real-valued random process f(t)=∑n=1Nanp(t−nT)f(t) = \sum_{n=1}^N a_n p(t - nT), where T>0T > 0 and N is a positive integer. Here, p(t)=1p(t) = 1 for t∈[0,0.5T]t \in [0, 0.5T] and 0 otherwise. The coefficients ana_n are pairwise independent, zero-mean unit-variance random variables. Read the following statements about the random process and choose the correct option.

Electromagnetics

4 Questions
GATE→2025→Electromagnetics→Maxwell's Equations and Plane Waves
Q62
MCQ[2 Marks]
A square metal sheet of 4 m×44~m \times 4 m is placed on the x-y plane as shown in the figure below. If the surface charge density (in μC/m2\mu C/m^2) on the sheet is ρs(x,y)=4∣y∣\rho_s(x,y) = 4|y|, then the total charge (in μC\mu C, rounded off to the nearest integer) on the sheet is
Figure for Question 62
GATE→2025→Electromagnetics→Maxwell's Equations and Plane Waves
Q63
MCQ[2 Marks]
An electric field of 0.01 V/m is applied along the length of a copper wire of circular cross-section with diameter 1 mm. Copper has a conductivity of 5.8×107S/m5.8 \times 10^7 S/m. The current (in Amperes, rounded off to two decimal places) flowing through the wire is
GATE→2025→Electromagnetics→Transmission Lines, Waveguides, Optical Fibers, and Antennas
Q64
NAT[2 Marks]
A 50 Ω50~\Omega lossless transmission line is terminated with a load ZLZ_L of (50−j75) Ω(50 - j75)~\Omega. If the average incident power on the line is 10 mW, then the average power delivered to the load (in mW, rounded off to one decimal place) is ______
GATE→2025→Electromagnetics→Maxwell's Equations and Plane Waves
Q65
NAT[2 Marks]
Two resistors are connected in a circuit loop of area 5 m25~m^2, as shown in the figure below. The circuit loop is placed on the x-y plane. When a time-varying magnetic flux, with flux-density B(t)=0.5tB(t) = 0.5 t (in Tesla), is applied along the positive z-axis, the magnitude of current I (in Amperes, rounded off to two decimal places) in the loop is ______
Figure for Question 65