Electronics and Communication Engineering
GATE ECE year:2021 PYQs
Build your understanding with focused practice from past exam papers.
Questions 41–50 of 65. Imported answers require independent review unless marked reviewed.
Question 31
Open questionECMCQ2 marksNeeds review
The propagation delays of the XOR gate, AND gate and multiplexer (MUX) in the circuit shown in the figure are 4 ns, 2 ns and 1 ns, respectively.
If all the inputs P, Q, R, S and T are applied simultaneously and held constant, the maximum propagation delay of the circuit is
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Open questionECMCQ2 marksNeeds review
The content of the registers are R₁ = 25H, R₂ = 30H and R₃ = 40H. The following machine instructions are executed.
PUSH{R₁}
PUSH{R₂}
PUSH{R₃}
POP{R₁}
POP{R₂}
POP{R₃}
After execution, the content of registers R₁, R₂, R₃ are
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Open questionECMCQ2 marksNeeds review
The electrical system shown in the figure converts input source current
to output voltage
. 
Current
in the inductor and voltage
across the capacitor are taken as the state variables, both assumed to be initially equal to zero, i.e.,
and
. The system isYour answerChoose one option.
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Open questionECMCQ2 marksNeeds review
A digital transmission system uses a (7, 4) systematic linear Hamming code for transmitting data over a noisy channel. If three of the message-codeword pairs in this code
, where
is the codeword corresponding to the
message
, are known to be (1100; 0101100), (1110; 0011110) and (0110; 1000110), then which of the following is a valid codeword in this code?Your answerChoose one option.
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Open questionECMCQ2 marksNeeds review
The impedance matching network shown in the figure is to match a lossless line having characteristic impedance
with a load impedance
. A quarter-wave line having a characteristic impedance
is connected to
. Two stubs having characteristic impedance of 75 Ω each are connected to this quarter-wave line. One is a short-circuited (S.C.) stub of length
connected across PQ and the other is an open-circuited (O.C.) stub of length
connected across RS. 
The impedance matching is achieved when the real part of
isYour answerChoose one option.
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Open questionECNAT2 marksNeeds review
A real
non-singular matrix
with repeated eigenvalue is given as
where
is a real positive number. The value of
(rounded off to one decimal place) is ________.Log in to check the answer
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Open questionECNAT2 marksNeeds review
For a vector field
in a cylindrical coordinate system
with unit vectors
and
, the net flux of
leaving the closed surface of the cylinder
(rounded off to two decimal places) is ________.Log in to check the answer
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Open questionECNAT2 marksNeeds review
In the circuit shown in the figure, the switch is closed at time
, while the capacitor is initially charged to
(i.e.,
).The time after which the voltage across the capacitor becomes zero (rounded off to three decimal places) is ________ ms.
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Open questionECNAT2 marksNeeds review
The exponential Fourier series representation of a continuous-time periodic signal
is defined as
where
is the fundamental angular frequency of
and the coefficients of the series are
. The following information is given about
and
.I.
is real and even, having a fundamental period of 6
II. The average value of
is 2
III.
The average power of the signal
(rounded off to one decimal place) is ________.Log in to check the answer
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Open questionECNAT2 marksNeeds review
For a unit step input
, a discrete-time LTI system produces an output signal
. Let
be the output of the system for an input
. The value of
is ________.Log in to check the answer
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