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GATE EC question library

Practise GATE EC Electronics and Communication previous year questions free. Browse by subject, syllabus topic, year and question type, with answers and available solutions.

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Official PYQ2025Control SystemsMSQ · 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).
Official PYQ2025Analog CircuitsDiode CircuitsMSQ · 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-M to MM?
Official PYQ2025Engineering MathematicsProbability and StatisticsNAT · 2 marks
Two fair dice (with faces labeled 1,2,3,4,51,2,3,4,5, and 66) are rolled. Let the random variable XX denote the sum of the outcomes obtained. The expectation of XX is __________ (rounded off to two decimal places).
Official PYQ2025Engineering MathematicsVector AnalysisNAT · 2 marks
Consider the vectors a=[11],b=[032]\boldsymbol{a}=\left[\begin{array}{l} 1 \\ 1 \end{array}\right], \quad \boldsymbol{b}=\left[\begin{array}{c} 0 \\ 3 \sqrt{2} \end{array}\right] For real-valued scalar variable xx, the value of min⁡x∥ax−b∥2\min _{x}\|\boldsymbol{a} x-\boldsymbol{b}\|_{2} is _____\_\_\_\_\_ (rounded off to two decimal places). ∥⋅∥2\|\cdot\|_{2} denotes the …
Official PYQ2025CommunicationsInformation TheoryNAT · 2 marks
XX and YY 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=1)=0.14P(X=1,Y=0)=0.24P(X=1,Y=1)=0.56\begin{array}{l} P(X=0, Y=0)=0.06 \\ P(X=0, Y=1)=0.14 \\ P(X=1, Y=0)=0.24 \\ P(X=1, Y=1)=0.56 \end{array} The mutual information I(X;Y)I(X ; Y) is ________\_\_\_\_\_\_\_\_ (rounded off to two decimal places).
Official PYQ2025Analog CircuitsDiode CircuitsNAT · 2 marks
The diode in the circuit shown below is ideal. The input voltage (in Volts) is given by VI=10sin⁡100πtV_{I}=10 \sin 100 \pi t, where time tt is in seconds. The time duration (in ms\mathrm{ms}, rounded off to two decimal places) for which the diode is forward biased during one period of the input is ____\_\_\_\_
Official PYQ2025Digital CircuitsSequential CircuitsNAT · 2 marks
In the circuit shown below, the AND\mathrm{AND} gate has a propagation delay of 1 ns1 \: \mathrm{ ns}. The edge-triggered flip-flops have a set-up time of 2 ns2 \: \mathrm{ ns}, a hold-time of 0 ns0 \: \mathrm{ns}, and a clock-to-QQ delay of 22 ns. The maximum clock frequency (in MHz\mathrm{MHz}, rounded off to the nearest integer) such that there …
Official PYQ2025Analog CircuitsDiode CircuitsNAT · 2 marks
An ideal p-n junction germanium diode has a reverse saturation current of 10μ A10 \mu \mathrm{~A} at 300 K300 \: \mathrm{ 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 mA100 \: \mathrm{mA} at 300 K300 \: \mathrm{K} is _______\_\_\_\_\_\_\_. (Consider the Boltzmann constant …
Official PYQ2025ElectromagneticsTransmission LinesNAT · 2 marks
A 50Ω50 \Omega lossless transmission line is terminated with a load ZL\mathrm{Z}_{\mathrm{L}} of (50−j75)Ω(50-\mathrm{j} 75) \Omega. If the average incident power on the line is 10 mW10 \: \mathrm{mW}, then the average power delivered to the load (in mW\mathrm{mW}, rounded off to one decimal place) is _______\_\_\_\_\_\_\_.
Official PYQ2025Networks, Signals and SystemsCircuit AnalysisNAT · 2 marks
Two resistors are connected in a circuit loop of area 5 m25 \mathrm{~m}^{2}, as shown in the figure below. The circuit loop is placed on the x−yx-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 zz-axis, the magnitude of current II (in Amperes, rounded off to two decimal places) in …
Official PYQ2024General AptitudeMCQ · 1 mark
​​​If ' →\rightarrow ' denotes increasing order of intensity, then the meaning of the words [ charm →\rightarrow enamor →\rightarrow bewitch] is analogous to [bored →______⟶\rightarrow \_\_\_\_\_\_ \longrightarrow weary] Which one of the given options is appropriate to fill the blank?
Official PYQ2024General AptitudeMCQ · 1 mark
​​​​P, Q, R, S\text{P, Q, R, S}, and T\text{T} have launched a new startup. Two of them are siblings. The office of the startup has just three rooms. All of them agree that the siblings should not share the same room. If S\text{S} and Q\text{Q} are single children, and the room allocations shown below are acceptable to all. …
Official PYQ2024General AptitudeMCQ · 1 mark
​​​​Five years ago, the ratio of Aman's age to his father's age was 1:41: 4, and five years from now, the ratio will be 2:52:5. What was his father's age when Aman was born?
Official PYQ2024General AptitudeMCQ · 1 mark
​​​​For a real number x>1x>1, 1log⁡2x+1log⁡3x+1log⁡4x=1\frac{1}{\log _{2} x}+\frac{1}{\log _{3} x}+\frac{1}{\log _{4} x}=1 The value of xx is
Official PYQ2024General AptitudeMCQ · 1 mark
The greatest prime factor of (3199−3196)\left(3^{199}-3^{196}\right) is
Official PYQ2024General AptitudeMCQ · 2 marks
​Sequence the following sentences (P,Q,R,S)(\mathrm{P}, \mathrm{Q}, \mathrm{R}, \mathrm{S}) in a coherent passage: P\text{P}: Shifu's student exclaimed, "Why do you run since the bull is an illusion?" Q\text{Q}: Shifu said, "Surely my running away from the bull is also an illusion." R\mathrm{R} : Shifu once proclaimed that all life is illusion. …
Official PYQ2024General AptitudeMCQ · 2 marks
​​​​​Four identical cylindrical chalk-sticks, each of radius r=0.5 cmr=0.5 \mathrm{~cm} and length l=10 cml=10 \mathrm{~cm}, are bound tightly together using a duct tape as shown in the following figure. The width of the duct tape is equal to the length of the chalk-stick. The area (in cm2\mathrm{cm}^{2} ) of the duct tape required to wrap the bundle of …
Official PYQ2024General AptitudeMCQ · 2 marks
The bar chart shows the data for the percentage of population falling into different categories based on Body Mass Index (BMI)\text{(BMI)} in 20032003 and 20232023. Based on the data provided, which one of the following options is INCORRECT?
Official PYQ2024General AptitudeMCQ · 2 marks
Examples of mirror and water reflections are shown in the figures below: An object appears as the following image after first reflecting in a mirror and then reflecting on water. The original object is
Official PYQ2024General AptitudeMCQ · 2 marks
​​​Two identical sheets A\text{A} and B\text{B}, of dimensions 24 cm×16 cm24 \mathrm{~cm} \times 16 \mathrm{~cm}, can be folded into half using two distinct operations, FO1\text{FO1} or FO2\text{FO2}. In FO1\text{FO1}, the axis of folding remains parallel to the initial long edge, and in FO2\text{FO2}, the axis of folding remains parallel to the initial …